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I can't get the picture of the trim tag to upload due to the stupid format that tis has been sent to me in, but the numbers are as follows..

69 12437 NOR298412
711 71 71
03E X77

Does this match the VIN? Seems a tad early to me.

Sorry about the quality of the pictures. These are from an aquaintance who is considering this car and is asking me about it's authenticity..
The car can be found here.. http://cars.oodle.com/detail/used-1969-chevrolet-camaro-for-sale/3308423637-cortlandt-manor-ny/
The VIN is said to be 124379N627673. The ...618 block apparently has a March 21 1969 casting date.
I don't yet know the build date and haven't seen the X77 tag yet, but this VIN should make the tag a 1st or 2nd week of April, right?

The engine number is very difficult to read, but the 3 appears to be slightly out of alignment.


The VIN number at the oil pad also looks to not only be out of alignment but the digits appear skewed.


Am I right to be quite suspicious of these stampings and therefore the car?

[I]

Did they use I instead of 1 in the VIN? Looks like 124379N599I07.

Apparently yes.. Most engine VINs used an "I"

AMK has it also

What page and part number please? My 2010 catalog doesn't list it.

Try American Auto Wire grommet part number 500179 for $4.
It requires a 1/2" hole and accepts an ~18ga wire.
Download their catolog and see pg 71 (2011)
I dare say that AWW use exactly this grommet on their tach harness'.
Classic Industries use the same part number and are $5.

4x U-bolts holding the axle to the anchor plates.. Resto oversight?
Shouldn't it be 2x U-bolts and 4x T-bolts according to illustrations in JL8-A2.

Thanks Scott. 

I have narrowed it down somewhat, and have found that the issue is most likely the line-lock that is installed on the subframe and is between the distribution block and the pressure regulator valve.
(Yes, I have mounted the line-lock on the rear system so it isolates the rears from working which gives me normal use of the fronts during a burnout.)
With the car warmed and the rear brakes holding on, cracking the flare-nut on the distribution block under the master cylinder, no fluid was expelled.
But when I cracked the flare nut on the inlet side of the pressure regulator valve, fluid was expelled and the rear brakes released immediately. The line-lock is in between.
This also proved that the flex line, wheel cylinders, park brake adjustment and rear brake assemblies are all OK.

It's a Moroso (44050) line lock and their manual says they are sensitive to heat. They aren't that close to the headers on my car, but the hot air flow from the headers would be warming the line-lock somewhat.
To see if that was the case, I made a small heatshield over the line-lock and it didn't eliminate my problem, but it did reduce it, so I think I'm on the right track. (BTW. The line-lock is creating the fluid restriction all while switched off.)
I will now consider options regarding the replacing, rebuiding or relocating the line-lock.

Thanks a heap to those who have helped me in this thread.

67s never had multi-leaf rear. 

Thanks Steve, I'll check it out..

Here's another thread on the proportioning valve: http://www.camaros.org/forum/index.php?topic=5952.0
Not sure why you think air being introduced into a hydraulic system will cause a pressure build. Air will cause less pressure. If you feel the p. valve is causing the problem, although it should not be, just install a bypass to test your theory. I don't put 100% trust in new part quality, your new flex hose could still be bad.

I am not sure if there is a pressure build up, but one of the causes of the brake pedal not returning is air in the lines. That valve can easily be introducing air if the upper ring-seal leaks.
I do intend on bypassing the valve. I will simply remove the guts of the valve and re-bleed..

I couldn't find the thread on the rebuilding of the pressure regulator valve (I don't think there is one yet) but I have found this by Scott Hollenbeck (username here is sah62)
https://www.musclecarresearch.com/kh-multi-prop-valve-autopsy

First of all, the repro valves don't have Tru-arc retainers, the thin washer, or the seal found in front of the said retainer on the lower stem of the piston.

My question is this.
Is the upper ring-seal on the plunger/piston supposed to prevent brake fluid passing into the lower part of the valve where the spring is located?
On the repro I have, the knobs who made it also fitted the wrong size lower o-ring and that caused fluid to pass out of the lower nut. I replaced the o-ring with the correct size and now all is fine regarding leaks.
So, if the upper ring-seal allows fluid to pass into the lower part of the valve, how can this valve ever work when an incompressable fluid is on both sides of the piston/plunger seal? -because with the lower o-ring leak that I had, it's quite clear the upper ring-seal is not a good fluid seal..

I also fear that this air cavity that originally exists in the lower portion of the valve when fitted is getting passed the upper ring-seal and into the rear system during use.

Adjusters are working fine. When cool, the drums slide off no problem. Also, if the brakes locked or dragged mechanically, no amount of time would "relax" them.

Once the system is bled, the pedal seems to return nicely for a short while, then it starts to stick more as if there is air in the rear line. (I am beginning to have suspicions of the pressure regulator valve introducing air passed the plunger seal and into the rear line. I might post in another thread that discusses this part.)
I'll check the park brake adjustment, but fairly sure it's not the cause of the dragging. When the brakes are dragging, there is very light resistance in the park brake pedal until several clicks toward the bottom of it's travel like normal.

I have an new replacement flex hose as I am aware flex hoses acting like check-valves like you say. The reason why I haven't swapped them yet is because the hose on the car is brand new and only ~3000 miles old.

Old fluid is out when the rear drums were rebuilt and refiited..

Thanks guys

One thing I have just found out (but don't he it necessarily being a contributing problem in my case) is the boneheads who make the repro pressure regulator valves, bore and hone for the plunger and then they punch the bracket on. ..in that order..
The bore on my valve was 0.020" out of round and the spring was binding with in it. I had to pull the spring out using pliers and force it back in.
I rebored it to 0.50" and now it drops in as intended and moves freely.

Hey guys, I am having the problem of dragging rear drum brakes that get progessively worse in stop go traffic. The associated symptom is that the brake pedal does not fully return. Lifting it with my foot often releases the dragging rear brakes.
After have them recently lock on and having no choice but to drive the short distance home, naturally they killed themselves with heat and I rebuilt them with new everything except 3000 mile old wheel cylinders which I checked and found they both moved freely in their bores.
I have also found that they drag heavily after they are warmed up and parking the car for around 10 mins allows them to release, so now I'm suspicious of heat somehow..
I even welded the backing plates' rubbing blocks and sanded them back to eliminate the grooves worn in them over time. I know the rear drum assemblies themselves are good. It would be an enormous coincidence for both rears to develop the same problem at exactly the same time.
This issue seems to have been present in the system since the car's recent resto debut, and since then I have...

Made sure their is ~1/16" clearance between the booster's pushrod and the master's piston,
Bled the entire system,
Replaced the EIS replacement master with the correct oe type (repro of the 5468165) from HBC. (Bench bled, yes.)
Installed a vacuum pump and tank that maintains ~20in/hg vacuum, (as the roller managed only ~8")
Swapped the brake pressure regulator valve with another new one.. This is the valve that is mounted on the subframe below the driver's seat.

The system also has a metering valve which was rebuilt and seems to work.
Do either of these two valves maintain a small amount of residual pressure in the line for the use with drums or is that the master's job? I know front disc / rear drums require it and the factory did it somehow.

Because most of the likely causes I thought have been replaced or eliminated with new parts, I'm wondering if anyone has had problems with these valves maintaining pressure in the rear line causing the rear brakes not to release fully.

The other component I am suspicious of is the 8" dual diaphram booster. It and the pedal mechanism have been checked for binding but they move freely.

Help!
It's driving me mental..

On 68s, is there a piggy back connector that comes out of the dash to 1/4 panel loom connector?
U29.. Hmm not in the 68 FAIM.. 
U29 in the 69 FAIM only shows the mounting of the lamps themselves..
UPC12 D3 in the 68 manual somewhat suggests what I have said above..