I'm one of those guys.
However, my 67 FB was/is all original except the intake, carb, distributor, stereo, and wheels.
This will be my factory #'s car with finished.

The GTO drive train is missing, and the car was originally yellow. Now it's brown.
All the jambs are great, so no spending the time or $ to change back.
Just make it a driver. Besides, it's not a FB

Heres the block codes i can use for auto trans;

yz, xw, xs, and ys(the most common).
Heads would be #16.
Intake; last 3 #'s 140 or 068.