I started an b18a engine swap out of a 91 integra into rex. I'm trying to find the b-series engine mounts for cheap and a conversion harness if necessary if any one has any ideas of what else I need to do or any of you honda gods can help me figure this mess out let me know ASAP!
If the rex is an HF or Si its plug and play. Just remove the old engine, install the new engine using mounts (http://hasport.com, cheap mounts break, do it right the 1st time), plug in the sensors, plug in the integra ECU, and drive away.
If you have a DX, you have to do the DPFI to MPFI conversion, which pretty much entails splicing in the wiring for 2 more injectors. There should be a write up on it somewhere.