Found this early 65 Dearborn Fastback at a local shop. Build date probably Nov 64 or Dec 65. No door tag, but sheet metal stamps I checked were 10/23/64 to 11/3/64, and steering box tag was and 11/5/64.
It has rivets in the lower two trap door holes on both sides, screws in the upper hole on each side. Interior is trashed. It's been siting since 1982. The current owner found it as is in '82 in another junkyard, so possible the rivets are original.