The JU87 in ground attack config shouldn't get F3. Heck, for that matter, neither should the dive bomber config, nor the A20, nor the SBD, B5N, D3A, etc etc.
A big bomber with a full crew scanning the skies in all directions? Sure, F3 is representative of the additional sets of eyes.
A dive bomber or attack planes crewed by 2 guys, including the pilot? We already can see everything the rear gunner could see by pressing the "2" key.