Not been on much lately and ive forgotten the colours

If you have what is actually an ecu off an 88 spec car its fine on a 90 spec, the only times you cause problems are fitting 87 onwards spec ECU's into 86 and earlier cars because they dont have a knock sensor wired in so the ignition runs permenantly retarded.

A series 1 ECU is actually the best ECU you can get as long as you have your car set up so theres no chance of detonation.

99.9% sure BLUE RED BLUE & BLUE RED WHITE are S1 ecu's so yours is a S2 ECU