Like everyone said, get another gauge on there to verify the pressure.
Why is the level high? Does it smell like fuel or antifreeze? Does it feel thinned down between your fingers?
Reason why I ask is that once my oil pressure dropped so I check the level and it was almost a quart over and smelled like gas. Turns out my carb was dumping gas into the intake and thinning out the oil, thus the drop in oil pressure and higher oil level.