Welcome to the Wire. Engine swaps is one of the more common discussions as far as mods go. Your best bet is to search past threads for starters, then post back with specific questions.

There aren't too many V8s as it requires far more cutting and fabbing. There are swaps with other Mistu 3.0, and turbos swaps for 2.6s. There are a few Chevy 4.3s out there now too.

Mistu swaps tend to work with the Mitsu trannies. The 4.3 swaps tend to use the Chevy tranny. Don't know what the few V8s used.

Big Truck: 00, 3.5, Endeavor, 5-Spd drive line in hand!
Little Truck: 87, 2.6T I/C, MT, LSDs, Tonneau Top
Her Truck: 03, 3.8, 20th Anniv, 65k
Daughter's: 06 Eclipse, Keeping it Mitsu!
FSMs: MitsubishiLinks.com