John.

I see you already have the rig talking.  Very good, but, I'll leave the
other message anyway.

Your best bet for rf grounding is to fool the radio with a counterpoise.
This wire should be a quarter wave length for the band you are operating.
Attach it to the ground connection on the 570, and simply run it around the
base board, along the ceiling, wherever you can get away with it.

As with antennas, a 40 meter counterpoise will work pretty well for 15
meters, etc.

Use whatever wire is handy, but stranded wire is best.

To figure the lengths, use 234 divided by the frequency.

The exact length may not be critical for a given band.

Be careful, though.  Even at low power, this wire may carry a significant
amount of rf which will get your attention if you grab it while
transmitting.

I use this arrangement along with a 50 foot end fed random wire which runs
out my second floor window and terminates in a tree.

I have to use an external tuner, the 570 won't tune it by itself.

What antenna are you using?

K5XU