The 6 cyl will make mince meat of that AX5
In addition to just slipping the new engine between the framerails..................
You will need to re-locate the engine mount brackets on the frame ( cut & weld ) . A couple of sundry items need to be replaced and or reworked , like drive shafts , transfer case and transmission , wiring , ECM , rad & heater hoses , power steering hoses ,exhaust work and radiator , to name a few.
Maybe a few other things I haven't thought of .