I'm just wondering what v8 engines are compatible with swapping into our truck with stock tranny?

I ask because I just got.my.truck back from the mechanic.and my mechanic.told.me theres a slow leak in the intake manifold and some point ill have to replace the headgasket, I have time but when i think about.it.there's no reason to buy another car in my.case atleast, so i was wondering if the lt1 Corvette .. or caprice impala motor would fit in the truck.. what v8 is most common in the truck?

 

its kinda limitless if your sticking to GM motors im gonna say most popular would be a 350 swap...it all depends on what u wanna spend both those motors mentioned would work