Original Crank - Anyone else had this issue ???

[GAR3598]

Original 1969 Z28 302 Crankshaft sent to machine shop and returned with there name and logo stamped in it

[bcmiller]

Did you ask them why they did that?

[169INDY]

Often times a Shop performing the Actual Crank work is different than most Auto Machine shops so They "Farm" out the work & are attempting to make sure yours comes back.
Kinda a Tracking sort of thing, Tags or  attachments get swapped or lost and a Stamp is like a Tattoo of sort.

Chrome plater Wholesalers Couriers are notorious for switching parts (i.e. Bumpers)

[GMAD_Van Nuys]

I still have the tag when Edelbrock Balancing Service Co. balanced the assembly for my Ford 289 engine.  Edelbrock marked the crankshaft "30403" with yellow paint and listed the following information on the tag:

Piston (wpl) - 21 7/8 oz.
Pin - 5 oz.
Rings - 2 1/16 oz.
Inserts - 2 3/4 oz.
Rod 19 1/4 oz.

I found this information about Edelbrock when they were located in El Segundo when I had them balance my engine assembly.

https://www.motortopia.com/culver-city-heroes/