Let me ask, before printing something stupid: are we all convinced that Rory57 is correct in posting, above, that the B-29's cowl "could not be removed to allow engine maintenance without first removing the propeller"?
I'm looking at a B-29 photo, a general shot and not a nacelle closeup, that seems to me to show enough Dzus fasteners to remove the forwardmost cowling section, and certainly the panels aft of that.
But I could be totally wrong. Anybody know better?