rwd 2.4L?

Neon engine, I guess? Planning on carrying the electronics and wiring over and running with the fuel injection? I'm thinking your best bet is an A body 7-1/4 with 3.23 gears and, make some frame rails, and take a leaf out of the 5 leaf 6 cylinder springs. Sometimes, you can find them for free here. Probably find something out of a Datsun/Mazda/Toyota that may work, too. Take some measurements and good luck!