I just bought a 89 crx si that has a d16z6 swap. but its wired the generic way. i suppose it has the stock pm6 ecu. no obo1 conversion. vtec on a button. no sure what dizzy. my question is im not sure how the engine wiring harness connects to the ecu, but could i get a 92-95 civic ex wiring harness and p28 ecu and hook just the engine harness into the ecu. I dont no if all the other wiring wires into the ecu to like light and stuff but if not would that work. And would i still need a obdo-obd1 harness.

 

VTEC on a button isn't a good way to do it at all, unless you plan on pushing the button at ~4800 RPM all the time... can't just push it whenever you want and get instant power.

You're headed in the right direction though, get the P28 and do it that way. I'm not sure of the details though.