1990 Talon TSI. I Recently got this, this is the wiring harness it came with.
Is it still possible to wire this in? Or would I need a new harness?

Sorry I’ll look at the archives and tech info later tonight. Just a quick question of how screwed am I?

you can wire in just get the plugs from http://connectors.sheridanengineering.com/index.htm

Wired mine on the living room floor, after modding the connectors from Sheridan Engineering (@brads), and plugged it in and she fired right off.

Tach mod is very important in the rewire. Mine is all plug and play thanks to those Sheridan Engineering connectors.

This is the write-up that I followed and it worked perfect.
https://www.dsmtalk.com/forums/showthread.php?t=203681
Marty

I might go the route of contacting Dynatek, and see if you can purchase the harness. It needs the little black box also, which I don't see in your picture. You would be changing the triangle plugs to square plugs for a 1990.