Sorry - An apology to you first.
Up to this point I did everything from memory, and it has been years since I played IL-2 Sturmovik.
I just re-installed it and checked.
I don't know what you did, but the Ju87 Stuka is not a flyable plane, and as such has no cockpit. It's an AI plane in IL-2 Sturmovik, and as such can't be selected in Quick Mission Builder to fly either. (only as an enemy plane, controlled by the computer). There are ways you can fly AI planes, but on external views only.
Several types of the J87 Stuka can be flown in IL-2 Forgotten Battles, but as stated above, that's an entirely different game. It's the successor of IL-2 Sturmovik with many many advantages Currently the latest version is 4.07. If you enjoy IL-2 Sturmovik and want to move on I would suggest buying the IL-2 Sturmovik 1946 version DVD - it will completely overwhelm you. It contains Forgotten Battles, Ace Expansion Pack, Pacific Fighters, Pe-2, Sturmoviks over Manchuria and 46'bringing you to version 4.07m of Forgotten Battles in one go. It has a LOT more planes, maps, objects, visual effects; oh well the list is allmost endless. You could say it would be a step from the Fort T model to the latest Dodge Viper
The manual for IL-2 Sturmovik Original version is in the main game folder in the "!MANUAL" directory. there are several versions in different languages.
Sturmovik 1946 is not available in the normal shops in the USA, but it can be ordered online through several online stores, like NWS Online store (see link below my sig), GoGamer.com, Play.com and probably several others by now. It just got delivered to them very recently.