Need some help determinting if I should rebuild my Avalanche 5.3 Vortex (which has a rod knocking @ 96k miles???) or put my rebuilt LS1 that has been sitting in the corner of my garage for 5 years in it.

I would put it in it in a heartbeat but, at this point, don't know what all is's not a conversion but a replacement; but will the computer work or have to be replaced, will the wiring harness plug in play...etc.

where do I go to find out what I need to know?