Thanks for the ideas, everyone. I could try both methods. Capo the favorite guitar on the third fret but also get the camping guitar out and lower it a step. (I don't play these guitars, I just own them.)

If you want to hear the piece we are doing, it is called Gray's Inn by John Coperario. Go to http://village.infoweb.ne.jp/~fwii3867/em/index-e.html and click on the title. We will be doing it slightly faster than the site has it. Again, thanks.

WYSIWIG: That was interesting about tuning the electric autoharp down a half-step. However, if one of us did that, we'd be tuning the other instruments all night. It must depend what instruments are in the ensemble.