For Pre-89 ECU's, there are yellow ECU connectors, 89+ are grey and of a differing style.
Pre-89 Turbo ECU's have 4 connectors, 3 on the ECU (24P, 18P and 10P) with one extra pigtail (6P) sticking out of it.
Pre-89 N/A ECU's have 3 connectors, all on the ECU (24P, 18P and 10P).
They are not...