I think the wiring may be the same. I do know that the plugs were changed in '92 when Honda switched over to OBD-1 on all of their cars. Before you go about just randomly splicing stuff try to get a wiring diagram for both a '90-'91 and '92-'93 and make sure that everything matches up. I have a '92 Helms manual so if you can find the '90-'91 info I can hook ya up.