YES, I was a Pontiac GURU at one time, hahaha...., all Pontiac Motors, 350- 455, the heads off one will bolt on another, all the blocks are the same, all except for bore and strokes. Waterpump off a 350 will bolt to a 400 or a 455, oilpans. EXCEPT for the HO's or the SuperDutys. Heads are...