Turns out I WAS able to get it insured in FL as an RV/motor home by State Farm. Easy peasy. The original problem was the address I gave them as. Mail Forwarding service (St Brendans Isle, Inc in Green Cove Springs). I called another SF agent (in Venice, using a friend's address there) and they jumped right on it! (Talk to Jeromy at Stanley Dean State Farm in Venice).
Now I need to take that to Tax Collectors office to try to get a FL title with RV/Motor Home on it!