Restoring a car without documentation

If it has bucket seats check inside the driver one for the buildsheet.
The trunk number, (and the radiator support number) will have 10 digits, and contains the shipping date, (and can help match the vin to the body): the year, first digit 8, the plant line, 1 or 2, then an 8 digit shipping order number. The first 3 digits of the shipping order # will be the scheduled shipping date, scheduled month/scheduled day.
So, if yours was built in 1968 on line 2 at Hamtramck on May 31, it should be: 82531xxxxx

We could get close to what options it came with if you have some good pics. I have a databook and some self taught knowledge on the 67/68 cars.