easiest...4.0...v8 requires a lot of mods....what r u trying to build? axles? tire size?
there's more to it that just dropping a v8 in it. there is a jeep in my crew with a stock 4.0 that can do anything the v8 jeeps can do and more.
in this video the red jeep is a v8 and the black jeep in a stock 4.0. both have 2.5 ton rockwell axles and 52" tires and pto wenches
Custom chassis. 468 full roller chevy BB . 5 ton 2" overson axles in 2.5 ton rockwell housings. 57" v-tread R2 tires, Custom fabricated four link suspension with ford coil springs and dual shock setup.