hi to all . i picked up a 89 1500 short bd. witha tired 5.7. after tearing the motor down ive found out both heads are cracked in the exhaust valve seat and port areas. ive gotten annother set of earlier model heads from a buddy but they are not the late style center bolt cover ones. so to keep my tbi set up ive got to modify the 4 middle intake man. bolt holes (which are at a different angle than the outer ones) so the manifold will bolt to the early heads. it looks like it can be done but i dont know if i can do it right. has anyone tried this before?