Could be be a worthy swap. There's a few cheokees rolling around with ls engines. They're becoming plentiful in junkyards, good aftermarket support, lightweight versions, multiple oil pan configurations, you can even toss a carburetor on if you like. Extra bracing would likely be needed, a light foot would likely be needed in 4wd as to not tear up the front end. Would I personally go this route? Not likely, the ls engines are expensive if something goes wrong, you have to pick your donor very carefully, there are some known bad seed ls's out there. I wouldn't attempt this swap without a complete running/driving donor, it would save lots of money in the long run (IE pick up a totaled out truck). On the other hand, I like do the idea, so don't get me wrong, lol.