What 6 cyl engines/transmissions will swap easily out of a 1992 Jeep Wrangler?

I am looking at a 1992 Jeep Wrangler 4 cyl that needs a new engine. I plan on using this Jeep as a fun-to-drive toy, but would like the power of the 6 cyl motor. Im not well versed on Jeeps. Ive heard newer motors fit, but Im looking for the easiest 6 cyl/ swap from a 4 cyl in a 1992 Jeep Wrangler. Any info would help! Thanx!