Peg, welcome aboard to the CRG
Know all of us sure wish you and your husband the best with the car but not sure what the trim tag or vin will assist in establishing it was a Dana unless someone has some Dana vin database. The trim tag on a 68 tells us very little as we own a 68. You mentioned it was purchased off the orig. owner and that you have the front end coming so maybe there are some clues there but so far I'm not sure anything has been revealed. I'm sure you asked but doesn't the orig. owner or any family members have any pictures of the car at all? Racing picture or maybe it never hit the track?
Again, welcome and good luck!