Need help 1995 mustang wiring

[bugz]

I was driving my car just died towed it home got a new ecu and it started right up so I thought it was a bad ecu so then I was driving it did it again so I thought it was my alternator so I put a one wire in and now my number 4 big fuse keeps blowing and the car won't start turns over but that's it please help

 

[Noobz347]

Verify that your [fuse 4] is for the "Air Bag"?

Pull codes.

Wild Ass Guess - Your Thin Film Ignition module (TFI) is telling you that it's time to go.