Electrical 1995 intake manifold ground issue

I'm sorry for asking so many questions recently. But I read somewhere that the secondary power ground goes from the back of the intake manifold to the driver side firewall. It is usually the culprit if your temp gauge goes up as you add load (turn signals, radio, etc.), which mine does. Does anyone have a picture of this ground on a 3.8L so I know where it is exactly? I can't seem to find the one on mine at all.

Thanks