Wireing Challenge! SOHC HUD S13 -> S14 motor and ecu

[Maeda]

So i'm swapping things over to a s13 chassis (lighter and OBD1).

Car WAS a sohc, but then an SR was put in. Now the SR is out and i'm sticking a S14 KA24DE-T in, and I'm keeping my s14 ecu.

Does this sound fishy to you? The gauge cluster won't hook up will it? HUD and digital speedo working, but will it work with the s14 ecu? The motor will most likely be a'ok?

Anyone foresee any problems i'll have doing this or any parts i'll need? It sounds almost silly and too easy a solution to me, that's why im asking...

I know this all sounds absolutely retarded but just humor me, i'm in QUITE the bind here...