There's been numerous threads about how to set the compass in the RAF fighters, running a forum search will yield results.
That being said, the compass on your instrument panel is not a magnetic compass, it's a gyroscopic one. The way it works is that you set it pre-takeoff to match the magnetic compass and then fly with the gyro compass. Once every 15 minutes or so, or after violent maneuvers, you need to re-align it because the gyroscopes drift and it gradually loses accuracy.
Check out this thread:
http://forum.1cpublishing.eu/showthr...highlight=hell
This doesn't solve the difficulty of getting the magnetic compass in view, so maybe we need a second "look at the instruments command" on top of the one we already have.
In the meantime, i've found that if i trim the aircraft well i can just disable head-tracking temporarily and pan the camera around with the mouse to get it in view and adjust it properly. It's not like i'm going to be worried about the compass mid-fight, such things are done during cruise to and from the target area, so it works you fine in the end. Also, you don't need absolute precision 100% of the time. As long as you are accurate to within 5 degrees (i think the gyro-compass drifts 2-4 degrees every 10 -15 minutes or so, depending on how much you throw the plane around) you can easily navigate by the map and looking at the terrain.