A mundane observation about the radio that nobody but me could ever care about;
Being a retired Galvanize worker, I was curious as to the stencil seen on the side of the radio case.
Rotating and flipping the image reveals the words "Long Ternes". Which is a lead and tin alloy coating... not Zinc and Aluminum as in galv. The case is essentially tinplate but with some lead.
The reason the stencil showed up in negative on this case, was that it was likely the facing sheet, directly above or below the stenciled sheet in a stack. The stencil transferred over to the adjacent sheet as it was still wet when stacked.