The 6 digit DSO suggests that you have a special order car (something on the car was not a regular production item)
The blank paint color code suggests that the car was a special order paint car. The original owner paid extra (not very much
to get the car painted a non- factory color. If you do a search you should find other discussions about the subject but basically the dealer/salesman would aim the buyer towards colors applied to other Ford products first then use the color chip book (fleet color book) if the other car line color would not fill the need.
Ford didn't keep records of what the color were for each car so you'll have to find a hidden nice example from the car to discover what color it was (often these cars are repainted a more popular color by PO's
That same number (DSO code) was originally in the upper left hand corner of the order sheet that the dealer used to order the car. Since the vast majority of cars were ordered and built (rather than purchased directly off the lot like today) the hassle of these sorts of special orders were not that big of a deal or problem though they can modify what was standard equipment in some years and models
I've owned about a dozen special paint cars - always fun and interesting. Sold my last one last year to another forum member
