Looks like maybe a Harrison Wildcat, or Ruttman Judge. I can't remember exactly what differs the two.. It's the rear fender mount some how.. Like the Harison is curved, as apposed to the Ruttman was flat accross.. Something like that.. I believe Lil Indian built one from that platform too..
If it is a Harison, Phil Harison is the guy you want to talk to. He could give you certificate of authenticity and vin number and all that jazz, and register as existing it the world..