I could not find any information on a 'Heller Chevrolet' let alone find a 'Gilford' Connecticut. I did find a Mannix Family Chevrolet in 'Guilford Connecticut:
Article about what the Mannix family is going to use the property for:
http://www.theday.com/article/20100520/N...mplate=zip06art
"The 23,000 square foot former car dealership was built in 1968 and has been owned by Charles Mannix, Sr., a General Motors dealer for 41 years, since 1991, Mannix, Jr., said.
Last year as the giant car manufacturer declared bankruptcy, General Motors closed 1,700 of its dealerships. The dealership tried to stay open as an independent, but it couldn't sustain itself, said Mannix, Jr."
Perhaps someone on here has some additional information or you could contact the Mannix family and inquire about a 'Heller' Chevrolet.