1970 340 Duster rare x car.

Trust me I am NOT trying to bust your bubble....I am simply presenting what I know to be the case re Chrysler/Plymouth /Dodge prototypes & special builds

I know a lil something after working at Chrysler parts as an inspector for over 10 years....we the inspectors had to personally check every part to print and hand delivered parts to lynch road and to highland park where most of the prototypes & special builds were made. Prototypes NEVER HAD PRODUCTION VIN tags or numbers from ANY assy plant..... they had prototype tags, period. For 20 some odd years were never sold to the general public, most of them were crushed, a very few escaped...a few went to Chrysler sponsored race teams..
Here is an example of a prototype tag ZZZ9ZZBOOOOZ1..... I have zero Idea what any of those number stood for...but I do know they were NOT able to get Titles and later had to be "re-tagged" at highland park before Michigan would issue a title

Your vin is from Hamtramck assy and has a sequence number meaning it was built ON the LINE, with everybody else's Duster 340