91 Miata Wiring Diagram

[93_Clubman]

If you've not already got access to the factory workshop wiring diagrams then this will help:
http://neomiata.com/garage/index.php Madracki wiring diagrams etc

But if you've already got them, then a bit more specific info might help as a few forumites have run Microtechs - indeed it might even be worth searching 'microtech' on here as this might have been answered before. Good luck!

[93_Clubman]

this ecu pinout list might also help:
viewtopic.php?f=76&t=38367

some possibly relevant microtech threads depending on which microtech you're using:
viewtopic.php?f=18&t=16983&hilit=microtech
viewtopic.php?f=55&t=33386&hilit=microtech
viewtopic.php?f=29&t=30255&hilit=microtech
viewtopic.php?f=29&t=17927&hilit=microtech

[93_Clubman]

here's a US MY '90-'93 manual trans ecu pinout diagram with a whole bunch of notes:
http://www.miata.net/garage/ECU_Pin-Out.png