not from that spot it doesn't. That's a spill on the outside. Any leak from the gearbox leaks into the tank or out the sprockets
hm, yeah looking at photos of the whole assemby dismounted.
it can only run into the inside. It is a bit like a tub that the gear box sits in. So what is that oil? running from the machine gun? A can of oil in one of the storage boxes leaked?
Directly in line with the stain there is a 5 gallon can on the front slope. I don't know what it contained in 1945, but in 1985, among other liquids, we were putting oil in them.