Ok, I can be detailed later because I’m right now on bed ( I’m in Spain, so there is time difference ). The interlock control box is aside the starter block system if seatbelts are not fastened also the warning systems brain control ( key in buzzer, seatbelt buzzer and light and lights warning buzzer on if equiped)
I can’t talk by memory the cavities used but this is how is wired the starting locking system (old diagram I made long time ago)
If you make to see how it works, the starting interlock system jump out can be made on several ways, but the easier are these two ways:
-splicing/jumping out together both yellow wires at reset button plug.
-swaping around the yellow traced with the solid yellow wire… either on cab side or engine harness plug.
both are totally safe and you wouldn’t need to despite the interlock box.
either of these methods, will feed the starting wire from ign switch straight to the relay despiting the interlock control box order to crank or not according with the seatbelt status. The warning system will keep in working order thought as far seatbelt and seats sensors harness are still plugged, which you can still keep in place and plugged. It won’t disturb anything. Personally I’m proactive on keep everything plugged and working if not really need to be removed for any failure reason.
if you want to learnt about how the interlock system works thought, check this video
however, without further details, I still think you got an incorrect forward ligthing harness (if not also the engine harness)
on a side note, your car was originally auto, so control box should have been blue… white are supposedly for manual cars
