I recently bought an '83 Chevy C70 that I'm trying to sort out a few problems on. One thing is none of the gauges in the instrument panel, except the speedometer, are working. I haven't dug too far yet, but wondering if there's a main junction in the harness at the firewall? Perhaps corroded contacts, etc? The wiring is a bit of a rats nest - well actually it had mice in it that the previous owner cleaned out before he sold it.