Rear view is correlative to your heads position. So your 6 view is relative to where your head seems to be in the cockpit.
So when you sit in your cockpit, standard forward view, pause TrackIr. Use the Arrow keys to move forward/backwards till you feel comfy regarding gunsight, cockpit and so on.
Hit F10 when sure this is it. Try to remain your head dead still. Reenable TrackIr and RESET your position. Now your head in game is matched to the saved setting. I believe your 6 view will improve dramatically.
Send me an email ( in my profile ) and I send you my TrackIr profile. I don't say it's perfect but it's a good base to start from. I can see my whole tail if I need, even my right elevator looking over my left shoulder
Remember, TrackIr is a very personal device! It takes time to work well for anyone.