I was browsing at a parts deopt...okay I was wandering around a junkyard

and I found an item I had not seen before. In a '41 to '46 Chevy 1/2 ton pickup, under the dash and bolted in the middle of the firewall was a metal box. This box was about 5 inches tall, 5 inches deep and 10 inches wide. It had a MOTOROLA emblem that ran vertically on it and a 515 emblem in the lower right corner.
I am guessing this is a radio of some kind...anyone have any information about what this is for sure and how rare it is?
Thanks,
Chevman