88 PU Wiring diagram needed

Does anyone have a copy of the wiring diagram for an 88 GMC Sierra?

Wiring diagrams are broken down into different systems on the vehicle. I cannot get you every diagram, it fills a large book. I may be able to access a few specific if you could narrow down what you need.

Thanks, I am having a problem when I turn on the headlights, the heater control sometimes starts turning itself on and off. I can turn it off and it will come back on. Of course it usually also goes to full cold, or vent and defrost, so it gets pretty cold in the winter. It does not happen when the head lights are off though.

I'll check at work tomorrow, see what i can find.