the first v-8 in any Cherokee platform was the 1993 ZJ, and yes it is MPFI. unless someone pulled the heads, intake, and the entire ignition system to swap in older LA parts it is still MPFI.
i did this exact swap in my rig. i used a 93 zj as the donor, the motor was originally from a dodge ram.
first point i would make about maintaining the auto trans and x-case is the sheer size of them. even with mounting the engine forward in the frame rails and adding an electric fan you are going to be looking at a rear driveshaft that would likely be shorter than stock.
if your not overly opposed to a manual you can use a mid 90's manual dodge dakota 3.9L bellhousing and a 231D or 231J (the dodge x-case would be preferred since it has the HD chain in it). with the motor moved forward as far as the electric fan and accessories allow, along with the installation of a SYE i had a 19.5" resting length for my rear DS with the d35 still in there.
motor mounts are easy. advanced adapters has motor mounts that are easy to get welded to the frame. i used a series of jacks and wood blocks to get the motor sitting in the desired position before fabricating the spacers for the motor mounts to be welded to. i made some cardboard patterns to gut the steel to and bingo bango motor was permanently mounted to the frame.
transmission mount is also easy. this is sort of a double whammy upgrade. find yourself some 1/4" plate steel and make yourself a flat skid. this is what is currently under my rig. it's not terribly pretty but it works.
this allows you to put your trans mounts wherever you please and gives you a truly tucked belly at the same time.
wiring isn't my strong point so i had jeff daniels jeeps do it for me. however, MoparFreak here on the forum was able to do all the wiring himself on a swap like this. maybe getting him a pm would help.
for exhaust you will need a set of shorty block huggers. long tubes will fit but you will curse the day you put them in after a short while. the heddman 318 block huggers have ports that will match the magnum heads if that is indeed what you have. an LA header will bolt up, but the ports are the wrong shape so it will not work efficiently.
i would also suggest a y-pipe and not trying true duals. i tried it and after a ton of wasted time and money i just made a y-pipe and went with a stock routing of the exhaust.
other than that it's really not all that difficult of a swap. you can maintain your stock fuel sender and pump, stock radiator will cool it just fine except a little creative hose routing will be required, and you can use your stock power distribution box from under the hood along with your stock gauges.
now getting the jeep to where your not destroying the driveline, that is another conversation all in itself. the ax-15 will take some minor abuse but not very much for not very long.