OBDII > OBDI conversion

I have this spare PCM and I want to put it in so I can "play" with the car. Problem is, I get all kinds of codes. I know I need to jump pin #21 with #22 and add in a 2K resistor for the O2's, but which O2's are these for? I have 4 of them. I want to put in the headers soon and don't know if the OBDI reads the pre or post cat O2's. Also, for the short term, what will happen if I just unplug the O2's? Will the PCM default to something, or will the car just run like crap?

Also, any experience on tuning software? Which one is better? I know I need to get an OBDI cable modified for the OBDII port. Opinions?

OBD2 added the rear (post cat) O2 sensors. So if you're doing an OBD1 conversion, those are the ones you will eliminate.

Unplugging the pre cat O2 sensors will make your car run like crap. The post ones, I think will just generate an annoying check engine light though. Easy way to find out.

Can't help you on the tuning software, sorry.

Robert, popping open the PCM case is really the hardest part. I did this conversion on my last WB4 and on Frank's WB4. If your PCM has been exposed to any salt/hard winters...it will be really white and no matter how long you let the bolts soak with Bolt Blaster...they will just snap.

I will be doing this again on my current '96 too.

These are the instructions I use

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I have an AKM cable for the OBDI plug BUT I snagged a plug from a '95 Fleetwood (just pulled the pins out of it) and will do the same with my '96 and put my pins in the '95 plug. (That make sense?)

Chris