Hi I have a 1988 c1500 stepside 2wd and am having some issues with the electrical system. At night when I turn on the headlights the entire dash goes dark except for the directional lights stay on constant, the high beam indicator light is on even though low beams are actually on, and all gauges except for speedometer shut down. Outside brake lights directionals headlights and plate lights work fine. Checked ALL fuses and relays and can't seem to find any broken or loose wires or connections. There is no dimmer switch on this model but not sure if I should start with the switch itself. Any help is appreciated! Thanks