Your 318 has a roller lifter camshaft, selection is limited. I chucked the injection on mine, I get much better mileage and power with an AFB on a hirise, but its a lot of work. Had to change Everything!
Any mods will throw the computer into a fit, and the '88-89 computer is a dog, can't be reprogrammed. Also its not available any more, so if it cashes in, you're out of luck.