Here is the pinout diagram of your OBD2a engine harness:
http://hondaswap.com/attachment.php?attachmentid=11

and a breakdown of the pinout functions is on this page:
http://hondaswap.com/reference-mater...pinouts-28667/

What I usually do to rewire since you are using OBD1 is snatch a wire that used to be for your 3-wire iacv, or one from the unused CKF sensor and just reroute it & repin it into the correct slot according to the diagram.

I'm not sure if you can get codes through the OBD2 port using a diagnostic, the OBD1 ecu I think it doesn't recognize. Might have to get them the old-fashioned way by bridging the service connector down by the ecu with a paper clip or piece of wire then count the blinks of the CEL!