That's how those VIN tags were attached in that era, my '63 & '64 were the same.
Rad support #s are same as bottom left row on fender tag: Sequential order # info.
Good ol' Calif DMV: still making things as difficult as they can.

Several places to decode the tag, mymopar.com & etc - Google's your friend.
Print & take as much paperwork as you can to the DMV to document the car.