I'm swaping from a b16a2 engine obd2 in my '99 civic to a b18c1 obd2 and was wondering if the ECU could plug right into the existing wiring?

Sorry I guess I could move this question to the swap forum if this isn't the right place.

 

What year is the Integra ECU?

If 00-01, then yes, otherwise no.

I would just ditch the OBD2 teg ecu, get a chipped VTEC OBD1 ecu, an OBD2B-OBD1 ecu jumper harness, bolt on some crap like I/H/E, and get it tuned.

 

Your harness is OBD2 B so you would need an OBD2B connector plug on your ECU. As MADMAX_zero, that would be from an 00-01 Integra. They do also have OBD2B to OBD2A conversion harness's to use the 96-99 integra ECU.