hey Mike , I am from that area (commute through Gorham daily) but short of knowing the rust prone areas on g bodies and basic car buying ( I have bought/sold hundreds over the years) I would not qualify myself as a turbo regal specialist but there is a guy I know in Gorham that is an appraiser , has owned a body shop there in town since I was a teenager at least ( I am 50) and has also sold and brokered muscle cars that whole time - I am sure there has been a turbo regal or 3 in his inventory over the years - maybe you could get him to do an appraisal on it for you ? Wyman's auto body , Joe Wyman is his name.
Website:
http://www.wymansauto.com/home.html