The L-Jet system is an electronic system and as such is much more involved than the D-Jet. There are sensors mounted in the flywheel housing for TDC and speed which may not be found on your housing. The L-Jet has an ECU computer which should be mounted above the glovebox. You'll need the engine wiring harness for the L-Jet system. If your current engine is anywhere near needing a rebuild, now would be the time to check the reputable salvage yards for an '80-'81 3.3L or 3.5L engine with everything attatched. Just my 2.0 cents worth, and there might be others out there who have done this. My experience was owning an '81 633CSi.