Intermittent opreation

[prestotech]

I have a 2000 C5 with what I believe is an intermittent ground, any help would be appreciated. Volvos, Honda motorcycles aks me, I'm lost on my newly aquired Vette without a wiring diagram.

Intermittently when starting the engine I'll get warning lights for the ABS/Trac system, at other times the climate control system will flash and the a/c quits for a period of time (up to 10 miles, more at times)then works properly for the full key cycle. I've inspected and cleaned the ground connections at both front frame rails.
I feel as if there is a ground problem but can't find the right grounding point.

[chris308]

[Rich Z]

Thanks for the diagram! And that reminded me that I wanted to ask Chris at Xtreme to check all my grounds while the drivetrain is being replaced.