Nick
As usual, great photos! The CU-145/ARC in the 8th row down, left is only the second ARC-21 coupler I have ever seen. Evidently RCA didn't sell many once the ERA 3000 coupler went into production.
They appear to be more rare then the ARC-21 itself.
I assume that your van was much lighter on the trip home?
Regards,
Jim
Logic: Method used to arrive at the wrong conclusion, with confidence. Murphy