Yea, it'll fit. Adapter plate to an EA82 transmission (better for offroad use), or use an EJ one (better for street use). Custom transmission crossmember. Some creativity/research on front axles. Wiring. Fuel Pump. Some Plumbing. It's been done many times, documented fairly well.
I'd call it about a 2 or 3 out of 10 as far as engine swaps. But I'm pretty well-versed in swaps (currently putting a Lexus quad cam V8 in my 4Runner, and did a lot of work helping a friend put a 6.0 LS in his '98 Legacy).