Well, this is another fine mess I have gotten myself into.... There was once a Viper Alarm in this truck when I got it. It sucked. I was cause choas in the truck, So I removed it. This was two years ago. Fast forward to a few weeks ago. I did to get a bunch of stuff fixed or upgraded in the truck before Tellico. I drove the blazer into the garage and started to work. I wired a 220v outlet in to the shop for my new compressor, swapped out the rear lift blocks for springs, converted the rear to disc brakes, etc. Then I started on the electrical. I have had a problem with the old battery isolator so I bought a Painless Dual Battery controller. It was going smoothly until I needed to find hot wire in Start and Run mode only. I climibed in the truck to find my wire. First thing I saw was the rats nest of wires under the dash. I pulled the old stereo and a bunch of wires from an old two way radio install. Then the part were I went stupid... I decided to remove the left over wire from the alarm. Bad plan. I should Have taken a few pics before starting at least or checked a wiring diagram, but no. This is what I have now. I have bought a copy of the 1991 Chevrolet Factory Wiring Diagram but it will not get here in time to make Tellico. Does anyone have a wiring diagram of that block in the first picture for a 1991 7.4L ???? Thanks for any help. you may now start laughing and pointing fingers at the big dummy.