We have a 109F4 here at the Canadian National Aviation Museum in Ottawa, and it is a really tiny little aircraft. I had no trouble looking in the cockpit (I'm 6'3"). In fact, it's hard to believe they could even fly with all those guns, fuel , etc. I doubt that I could fit into the cockpit. Couldn't fit into a spit either, for that matter. The P40E looks nice and roomy though.
The biggest WWII plane is the Lancaster bomber. The tires are like 6" high and the wing is 3 or 4 feet thick. It looks like a flying airbrake. Hard to believe that they could get airborne either. The B24 is fairly bulky as well, but sits closer to the ground.