Swapping a Chevy V8 into a Jeep is entirely worth it. You can do it on a budget or you can blow as much money as you want. It's not all that hard if you know your way around your tools.
Use the Novak Chevy engine mounts to put the engine in. It'll let you customize where it sits in the engine bay. You'll need to weld them in but the flexibility they give you makes life a ton easier. You will need to get a conversion radiator but you'll want a bigger radiator than came with the 4 banger anyway. They're not expensive.
If you like automatics, the 700R4 is hard to beat. You'll want to push your engine forward a bit to help make room for it in the YJ but that's not hard to do. The 700R4 bolts to the Chevy engine with no modification. A shorter alternative is the TH350. It doesn't have overdrive like The 700R4 but it's nice and compact.
If you like manuals, the SM465 is a good choice. It came behind Chevy engines so as long as you get the bellhousing with it, it's a bolt up with no modification. If you can find one, the NV4500 from behind a Chevy is also a good choice. It usually needs some minor fixes to stock flaws but a good rebuilder can do that for you.
For transfer case, a Chevy NP241 is a great option. It will bolt right up to any of those Chevy transmissions with no expensive adapters and it even drops on the drivers side (except for the first few model years). You'll probably need to put in a SYE to make the drive shaft fit but there's plenty of good options for that.
As far as axles, plan on replacing the factory axles. The D30 and D35 will never hold up to a V8 with 37's. A front Dana 44 built right can do it. A D60 or custom 9" with D60 knuckles would be better. In the rear, a built D44 would be adequate but a 9" or D60 would be better.
You'll want to gear the axles to match your transmission (with or without overdrive) and tires. But that's not hard to do, especially if you go with custom built axles.
As far as fuel injection, it's not hard to hook up factory throttle body ignition from a late 80's/early 90's Chevy V8. There's a ton of aftermarket options available as well. It all depends on your budget. You can go with inexpensive throttle body systems to full self tuning port injection. Propane is an option that some people have a lot of luck with. But consider that the Quadrajet carburetor on Chevy engines is probably one of the best factory carburetors for off roading out there. It's not perfect but it does really well for a carburetor. If you're on a budget, you can leave the Qjet on and do plenty of wheeling while you save up for fuel injection.