I'm having problems with my fiance's GTA. The battery is fully charged,but when you turn the key, you get nothing, not even a click. the headlights are also not functional, but the parking lights eventually turn on. What is going on here, It has to be a bad ground. The engine ground seems OK. Where is the firewall and frame ground on a '88 GTA?

 

Not necessarily; although it could be.

It's a bad connection, somewhere. Could be in the positive side of the wiring as easily as the negative side.

There's a small wire that comes off of the negative battery cable at the batt terminal and hooks to the chassis. That's the main ground. There's a ground strap between the rear of the pass side head and the firewall.

Your problem sounds like a bad battery cable connection. Check the connections both at the battery terminal, and where the cable hooks to the starter.