Just as a note, there is another way other than a multi meter to check for loose or open ground connections. Use a 12 volt light probe. With it connected to a known good battery ground, touch around the bare wires and look for a light. While it cannot not give you an exact ohm reading, at least you can find an obvious open circuit that is supposed to be grounded..

Using that procedure is better than using a multimeter because a multimeter will not subject the tested path to a load, which the filiment of a bulb does. Occasionally a connection(especially an old one, will ohm out good, but fail when a load is placed on it.

Will

That's weird... Ocasionally, I'll hear a relay click on or off when I have the key set to ACC. Maybe I have some loose or intermittent grounds.

I found another ground connection on my 280Z. It's under the passenger seat, next to the relay. Don't forget about the ones on the steering column for the headlights & the rheostat.

rear section, right behind the license plate frame...

Is that accesible from the inside of the car?

thx