One step forward ...
I posted for a plea for help to the Facebook Commodore Amiga group to see if anyone out there had the original manual for either card I'm dealing with. Two guys sent me stuff for the G-Force 30 (the more desirable card to get working, frankly). One was actual photos the the G-Force's manual. The other was a link to the manual, except it was the Series II (wrong one).
The photos are golden, though. I can at least check the jumpers from the real thing now! That's major progress regardless of what happens next.
UPDATE: The pics from the manual revealed 2 improperly set jumpers. !!