Out of curiosity The 91-94 S13’s pretty much had the same components as the Sr20 powered S13’s in Japan correct? Meaning the sub harness for the electrical should line up and be pin to pin? Which I doubt for you still have the re-pin the wires from what heavy throttle is saying.
Now my question is since the 89-90 S13’s had a different design like the CA18’s then would swapping out the Sub harness for the 91-94 s13 eliminate the work of re pinning the harnesses?

In other words if you have an 89-90 s13; rather than re pinning the harnesses, would an alternative be is to replace the sub harness with the one you get from the clip.

Again with the speculation you bought a front clip.