Interesting how many people opted for the optional oil bath filter. They are everywhere! Its very hard to find the 'stock' non oil bath cleaner. Must have been a really good sales pitch for oil bath at the time.
I think that very few 3100 A-D truck buyers opted for an oil bath air cleaner.
In VA in the late 60s and early 70s I worked on many A-D trucks. I never saw on oil bath air cleaner on a 1/2 ton A-D truck 216 engine (or on a 1954 3100 235 truck engine).
I also never saw a 5-window cab, nor a deluxe heater. Perhaps the more desirable parts/cabs are the ones that have survived?
The Task Force (and later) 235 engines, which were the most commonly used replacement engines in the older A-D trucks, would have had standard oil bath air cleaners. That is what we see today?