I own a 1996 blazer 2wd and am wanting to swap in a 5.7...now i know that a 96, 97, 98 would be the easiest but those are hard to find around here unless the have 250,xxx on them....so my first question is does anyone know if i can simply swap the intake onto an older block provided I used vortec heads?

 

Nope. Different bolt pattern. The Intake manifolds changed when the vortec engine was introduced. It went from a 12 or 14 bolt (my memory fails me) to a 10-bolt.