Joel did like to use the ford mirrors probably because they were pretty modern looking for 1969. He also used the "GT" letters from ford mustangs on the back of the GT vettes he sold and mine has ford mirrors on it too.
You should look for build sheets under the seats and or dash. Try to locate a detective that could run a NCIC trace to see who the originating dealer was that sold it and any previous owners names.
Lastly beg and plead with the girl to just one time give you what she knows.
You should post the trim plate info on here and the vin as someone just may help you.
I know what you are going through as I am doing the same thing on a '69 vette myself.
