At least according to the photos I snapped last year in the area, it appears late September and very early October are the best times:
OCTOBER 2 (Chalk Creek Canyon):
SEPTEMBER 29 (Near Cottonwood Pass):
SEPTEMBER 28 (Near Cottonwood Pass):
SEPTEMBER 24 (Near Independence Pass):
SEPTEMBER 19 & 21 (Near Cottonwood Pass):
Have fun and do give us a trip report afterwards!
"I always wonder what folks in frozen lands will think when they discover that hell is full of grass yards that need mowing every day and heaven is a blazing desert."
- Joel Smith