The engine harness will swap right into the LX. You will have to swap over the tachometer. I can't remember if the 4 banger tachometer will even work after the V8 swap. Even if it did it won't read correctly. Monster tachs are more accurate, but unless it's a dedicated race car those monster tachs are just beckoning thieves to break in. Plus, they're tacky if the car is mostly stock. They scream out "wannabe." If you're going mass air you can wire in a MAF sensor harness by moving a couple of pins in the EEC main connector. You'll need a MAF sensor bracket, and inlet tubing. You'll also need to unhook the hose going to the MAP sensor at the firewall after a mass air swap. Cap that hose off or the port under the intake for that hose.