99ls Into 99 Ex

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hey guys-
A buddy of mine bought a 99 LS swap for his 99 ex. We are having a bitch of a time with the wiring. Mounts are all set.

If we use the civic harness, what needs to be changed?

the o2 sensor doesn't plug in, the distributor has an extra plug, and so on

if we use the LS harness, there's no way in hell that its going to reach the ECU through thr fire wall.

If anyone has done this swap, please let me know any info you have ASAP.

Thanks in advance
Sorry, never done it. I don't know if it helps, but if the Gen 3 Integra is the same as the Gen 2, the wiring harness is in two parts. The part that plugs into the engine connects to the parts that plugs into the ECU at the firewall.
if you extend the wires from the ls harness would that work?im sure you thought of that im curious myself
yeah- its lookign that way. civic harness, swap the dizzy harness figure out what the two extra wires on the LS are for... swap o2 harnesses...
the two extra wires are for a sensor by the oil pump I think it's a top dead center sensor or something. you don't need to hook it up. It's on my B20Z too, just ignore it.
I put a 99 Ls in my 2k hatch and to get it wired up, I had to send the harness off to skunk2 and get an ecu jumper.