I have a 2000 5.3 and I was wanting to upgrade cam and heads before I put the radiator and fenders on the 72 chevy truck. I want to get the best bang for my buck and I was looking at some ls1 casting#243 heads and a comp GEN III/LS1/LS6 350 Xtreme RPM XR269HR Cam and a stall to go with it all. Just some input would be helpful cause I know some of you have been down this path before. Thanks