This is a known issue, as the stealth is a bit too heavy for, as mentioned, cheese (more likely a soft cheese like brie :rasp
mounts.......
I sorted mine by loosening the clamp between rear and mid section, and loosen the rear box strap (that the rear hanger is attached) and rotate/twist the rear section, looking from the back to the front of the car, in a clockwise direction. Then once you are happy with it, and it is hidden enough, tighten the clamp and strap up again.
The rear box should now be 'higher' under the bumper.......
Many people also go for the cable tie fix instead, which involves putting cable ties through the holes to hoist up the centre pin...........this can also be improved with some tubular metal inserts, much like those that are pressed into bushes. Basically you are looking to bulk up the holes within the rubber hangar so the centre pin is held higher........cable ties are needed for this too!
Hope this helps!?!
Rob