I've seen a few people ask questions about how to wire in the harness for a B16 swap. First things first, if you already have an Si/Hf, you already have multi-point injection. If you have a dx, you must first convert to multi-point and then continue.
Once you take out your motor, disconnect your harness and plug that harness into your B16. There will be some connections that wont be there on the B16, but you dont need them.
All you need from the B16 harness is the following four plugs: the one that connects to the knock sensor, 2nd 02, vtec and oil pressure switch. Cut those plugs from the B16 harness with some wire left over because you need to extend these four wires to the ecu. You will have to extend the wires a little.
Here are where they are located and the place at the ecu to connect them.
2nd 02:
Knock Sensor
Oil Pressure and Vtec Switch
The oil pressure has two wires. The black one will be the ground wire.
I hope this will help some people out.
Good Luck,
Julian