Even if you were putting the p/s on an earlier ('66-'67) model Big Block Chevelle with a short water pump, I still don't believe it would work. If I remember correctly (personal experience with similar swap in 1981), the "B" body's mounted the pump lower on the engine than the "A" body. The Chevelle's p/s gear box is in the way. I think that the "B" body gear box is behind the crossmember.