Never did get round to posting about my trip back in February.
I'm jealous that you got to go into Furnace Creek - we couldn't get there as I don't have an IR and there was a huge storm hanging over those mountains West of Vegas (it dropped around a foot of snow overnight apparently) so we headed East into Utah instead.
The only destinations we had in common with you were North Vegas and Grand Canyon. I too did the overflight of the canyon north to south after flying across southern Utah. Didn't worry too much about what'd happen if the engine quit - kinda not much point really, although I suspect there's probably only three or four minutes where you couldn't reach one rim or the other.
Anyway, can't wait to see a few pics. I must get round to posting mine at some point (warning of imminent thread hijacking).