Good advice from NOYENKO also....if the timing is wandering, or "sticking" at full advance, your engine will run erratic. Like he posted, very easy to remove from the equation. BTY, CHP was very
fair on the price when I had my distributor gone through last year. Plus certification
Heed Gary's advice on carb replacement or rebuild. Food for thought, while your carbs getting refurbished, whatever, you do not need a high dollar carb to feed that 302. Sounds like you are just out to cruise. Don't think any no lift 7800 shifts in your car's future. Check Summit, they carry refurbished Holleys and Edelbrocks. (street avenger ?) You would be surprised the overall
performance a 600 Edelbrock does atop that engine...just to tie you over.
Also check out Crane Corvette if you are pretty set on another 780 ,look to have a good rep and descent prices, see what they say.
I cannot see putting out $700 for another carb, when you own the born with...new base plate, metering blocks, neoprene gaskets, blow out protection, needles and seats etc,,would come in half that...