Can anyone tell me what the big wiring harness under the rear seat on the drivers side is for and where i can buy one? I've searched everywhere for it and can't find it anywhere. most of the wires were melted in a small fire and need to be replaced.

 

I'd have to see what you are referring to but I can tell you that the only way you will find that part is to find a salvage yard car that is identical to yours. You must know what functionality you don't have. The cheapest way to fix this would be to start splicing.