Since you're already going to replace the entire engine, it probably wouldn't be too much more work to simply replace wiring harness. If you can't find one for cheap, you can wire everything up to your existing wiring harness. I know for obd1, you can buy a subharness from Rywire or eBay, but I haven't seen anything like that for a y7/y8 swap. They might be the same, but I'm not sure.

You'll need to wire the following things up:
- VTEC solenoid
- VTEC oil pressure sensor
- knock sensor (assuming you're going to use the P2P ECU)