T18/T98 swap?

I don't think Mopar ever used this transmission in it's trucks so there's no OEM adapter. Novak might be able to help if you call the but they don't list an adapter. They do have so useful info on their site The Novak Guide to the Borg-Warner T98 Transmission

If it were me I would use a NP435 or similar from whatever Dodge truck you get your engine out of. I also wouldn't go too nuts engine wise. A stock 5.2 Magnum with EFI would be my pick. A bigger more powerful engine will use a lot more fuel for a little gain in performance. A Jeep 4.0L would also be worth looking at if you already have a 232 in there. The 4.0 will make plenty of power, has EFI, fits in the hole well, and loves to run 3000+ RPM where the 230 OHC starts getting fragile.