Wondered if this would be useful for those building or detailing the Wright R-1820 engines of the B-17E, F, Gs. (Really helpful if you find interpreting still-photos and schematics to be difficult!)
It's from Periscope Film on YouTube, and is 20min long:
It's a training video for mechanics, in black and white.
(Interesting too: eg near the start, an engine is unwrapped from thick, clear plastic - didn't realise that was happening then.)