it is illegal to convert a car to a previous OBD
depending on where you are located you could end up with a car that is no longer road legal
the plugs for the injectors, distributor, and alternator are different between OBD-1 and OBD-2
swapping those plugs or parts will have you good ont he engine harness side
you will (may) also need to lengthen a few wires to reach on the B series
then you will need a conversion harness to plug in the OBD-1 ECU to the OBD-2 ECU harness in the car
but as i said if your state has or ever gets emissions testing you are fucked