Prelude OBD1 conversion for auto trans

Ok guys, i need some help. I have a 99 Prelude with an auto tranny... yeah yeah i know. But i'm tying to convert it to an OBD1. I have a JDM P13 ecu for an auto but a normal conversion harness won't work. I've tried it. Someone told me i had to switch the at control unit and some people say my stock one will work. I know i have to get a special conversion harness for an auto. does anyone know who makes one and if my stock at control unit will work with this. What do i have to do to convert this to an OBD1? HELP ME PLEASE!

why are you converting to obdI?

I want to switch for the same reason everyone else does. The obd1 supports mods far better and will get rid of my check engine light due to a punched cat. Also, the obd2 detunes my engine and leans the mixture if i'm burning too much gas, which sucks because i have a fuel pressure reg on it.

http://www.ntpog.org/mods/fifth-afc/ecu.shtml

hope it helps