Si, will work, but you don't NEED to use only parts from an EG si

Integra axles work fine.
I have a GSR wiring harness
LS throttle body, and linkage, and brackets.

A salvage yard is going to become your best friend.

One thing I'm not too sure about, he has an OBD II engine, does he have to use OBD II sensors, or will a OBD I ECU overide all that?