Thanks for the comments guys
The Cherokee has a 4.0 liter straight six engine, not a V6, and I could only swap it with AMC's V8. Anything else would mean having the Italian DOT guys keeping the car for a month just to "test and inspect it", including disassembling the engine and dyno-testing it for HP rating, testing brakes and what-have-you to see how it copes with the increased horsepower... in short, "maybe it could pass as a one-of-a-kind prototype"
What?!!! Gotta be outa your mind!
So, I was hoping in a blower of sorts that'll fit, or something like that, or special pistons and cam and rechipping the ECU.
Anyway, I'm still haggling for the car, so who knows.