Yeah so your using the white plug on the rear loom in the grey fenale plug on the dash loom? I had mines like that too but swaping out for the turbo loom solved my issues and everything works. Mine was a 96 rear loom and it wired into my rear lights and fuel pump without modifying it, my cars a 99 so it might be a straight swap.
I would get you a pic mate but ive just refitted the interior and i dont think ill get time to pull it apart again. The turbo rear loom will get you running, i guarentee it