So I'm swapping the motor in my super sweet 2000 Blazer 4x4 and my donor engine is from a 1999 Astro van... I've seen other people do the swap and as heard it's completely compatible. my original motor has different rockers..?? To make this quick 4 months after I bought this truck the oil line pop out of the radiator and the motor was toast. There was a few things the old owner didn't tell me about like the fact the motor was completely rebuilt new almost everything but block. There's many things I want to swap now I'm not sure if I can swap these pushrod and rocker arms does anybody know????