You should be able to set your head position with TrackIR by moving your head where you want it then pressing F10 to save the position.
For example to raise your head you can put some cushions on your chair then use F10 to save the new higher position, then remove the cushions.
You can also get the same effect by slouching down in your chair, pressing Tracker Center, then sitting up straight again.
You can also use Tracker Center to reduce neck strain. If you get in a long turn fight and get tired looking up and you don't want to use hat views to override TrackIR you can look down, press Tracker Center, then look back up without strain. To return to your normal view just press Tracker Center again.