Now this is gonna seem complicated, but I've got a 77 C-10 with a 250 and a column shift. I've got and 82 with a 305 and a 91 blazer with a serpentine belt that I want on the 82 before I pull the motor on it. 2 problems- I can't get the ps pump and bracket of the blazer and I'm not sure if my 91 alt will work. I'm thinkin about pulling the pulley of the original alt but I still can't figure out this pump...