Well, it's being odd to me, so I'm submitting it here for comments. Here's a link:
The reporting mark is "USA 499051". The photo was most likely taken between 1953 and 1956. The tank is a T43E1, later an M103.
I'm puzzled that it's not "USAX" instead of "USA". And I'm puzzled that the car doesn't show up in the ORER, at least in 1950 and 1956. Interestingly, the car number is quite similar to the NYC series for flats.
So, what is it? And does it have any siblings?
Any and all assistance will be appreciated,