ok, pretty much for engine components, any GM '99-04 3400 V6 will work, examples: Chevy Malibu, Monte Carlo, Lumina, Impala, Venture; Pontiac Grand Am, , Aztek;
Now, as for misc. mechanical parts, any N-Body (Grand Am, Malibu, Alero) and some J-body (sunfire/cavalier).
About the only things that aren't interchangeable on the N-body are outer body panels, and most interior.
__________________
|