Or, you can go into your video settings screen for AH2, and check the box that says "show all resolutions" and then select the native resolution of your screen. Be aware though, at widescreen resolutions, your field of view remains the same, so things appear just a bit closer than they do in "normal" screen mode, so you need to adjust lead and timing accordingly, but it's not too difficult.
Also, there is an apparent bug with the F4U in widescreen, I can adjust my head position back to get roughly the same spot I was in before, to see most of my instrument panel, in all planes except in the F4. In those, I appear to be "stuck" about half way back, and can only go forward from there.
Planning to post a bug report about it soon, after I finish trying various work-arounds.
Blackwulf