If memory serves me right, there should be a connector in the main wiring harness, under the floorboard, on the left hand side of the machine. This connector connects the lower chassis wiring harness with the dash wiring harness. That connector gets corroded & burnt. That's where I'd start.
I can not get fire from the battery to the ignition switch or the lights ,horn and the amp light. any help would be appreciated.
This might be a tough one to find. What is the problem with your truck??