Outer Limits 4x4 Board

Hello I have some question but first of all I must warn you I don’t know anything about mechanic staff so be easy on me. I found a jimny cabrio in a very good price and I’m thinking of buying it but his engine power is too low and I want to change it. I made a search and saw that some of you have change Jimnys engine with Vitaras. I saw also that some have change it with swift. And here is my first question. I can change his engine only from another 4x4 or a can change it with any engine that can fits? If the second it’s true is there any possibility to put a engine like vw tsi? Which other parts do I have to change? If I buy a gear kit and put it with his current engine if I change the engine do I have to replace them too? Do you have something to propose me? Thanks

with reguards to the engine swap ask an engineer what mods have to be done to the car and what engines he will pass- bare in mind that every engineer is different eg; one engineer may let you put in a big block chev(not really, example only) and another engineer may tell you a vitara engine is to big..... so ring around.
with gears, if you put gears in your t-case and you use the zook case in the conversion then you will still have them...... likewise if you change the diff gears.....