Yes, the "red lead" was an undercoat, the bottom was black. Measure 9 the whole boat was black, Measure 32 the top dark gray.
The prewar boats were a light gray above waterline, and had huge white numbers with black drop shadows, but when war broke out and the boats were painmted black, they just painted obver everything. Presumabley the numbers would be slightly visible closeup.
The shafts would be painted too, but they would have wear near any bearings.
The props were painted I think.
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