Overflight of Grand Canyon

[sarboy w****r]

I'm off to do some fixed wing hours building in the US later this year. I see from a chart that are special rules for the airspace over the Grand Canyon, but I can't find out what these are.

Does anyone know what these are? Has anyone been over the GC, and do you know whether it's possible for a single engine aircraft, day VFR?

Thanks,

SBW