There are a few things to consider, first people racing gen 1 Neons run K car axles and hubs because there stronger. The transmissions are stronger too. Much of the parts interchange. So the best way to go is to use the best combo of parts, not just outright add all Neon stuff.
Get a Neon OBX, Neon B&M short shifter, and booger bushings. Then add them to a Dodge Shadow 2.2 523 trans with Shadow shifter and cables. Then use 88-90 Omni auto trans axles and mod a 5 speed L body bracket to fit the bolts on the mount. Then weld a tab on the K member for a later adjustable rear poly mount. All the same work to add the newer trans to the L body. Important mounts like the front mount and the trans mount line up right though.
Then the bolt the 2.0 to the 523 with a adapter plate, cheap.
here you see the plate you get that shows where to port the trans and the difference between a Neon and a 2.2 trans, 1 bolt. So you bolt the 2.2 front mount to the 2.2 trans, then mod the front bracket to bolt the Neon front hole to the front mount. In my case I'm using the SRT 4 engine with lower shield so the front mount hole is of little use.
Then when it comes to knuckles and hubs. Use Daytona struts with L body upper mounts, ground control coil overs and 3/4" of washers on the ends of the struts. Then you can bolt on 11.3" vented disks from K cars or mini vans. Or just bolt on the mini van 10" brakes to stock L body stuff. Unless you go clear to SRT 4 struts your not gaining anything, SRT struts allow the use of Willwoods 12" brake kit.
I would run Megasquirt because it is easy. But if your looking for the cheaper harder way the pin outs for Neon wiring are out there. Also add a 88 up Omni FI TBI fuel tank with turbo pump / bracket to the Rampage and your there.
Putting it all in there from the Neon would be a fun challenge but your talking about the most modded plateform in FWD Mopar history, the L body. So there are many many directions you can go. Add just the SRT 4 turbo to the stock 2.0, then Megasquirt it and add the SRT 4 intercooler up front and 8 PSI of boost. 13 second ride with nice mileage, right now, yesterday fast boost too.
Personally as you can make V8 WHP super cheap and easy with boost, and your fab skills. I would back half the Rampage and run the 2.0 with turbo bolted up to a A999 trans with an 8 3/4 out back. Swap the knuckles and move the rack forward like the old MP RWD kit. A stock SRT 4 long block is very reliable at 400 WHP with good tuning, that much WHP with a V8 is expensive without the bottle. Then your talking a MASSIVE weight reduction over the V8 weight. Aluminum driveline with aluminum 8 3/4 rear. Aluminum 4 link, lighter 999 trans with low first gear. 2400 lbs even in street trim, lighter with more weight savings.
A 2.0 NA has low rewards, so I would go with the easy swap parts doing it FWD. RWD with the right skills would have high rewards with a little boost. How good is a 2.4? One guy here went 4 years at 638 WHP on a stock long block and you can pick up the short block BY HAND and carry it. My 440 block in the garage with nothing in it weighs 230 lbs.......