Here is the thread that was started quite a while ago. But until they either come up with pictures, or the dna of a grizzley it is all speculation. I know of hunters that see a big brown faze black bear and swear it is a grizzley just by its size. A good test to tell the difference is on the Montana's gane and fish web site. You have to pass it to get a bear license.
there have been reports of Griz in Colo for years, back in the early 80's, when in collage at Durango, spent a lot of time around Wolf creek, the old timers up there (made friend with a old, old goverment cat hunter) said there is good population on Griz up there. There was a gris killed by a bow hunter in the 80's in the San Jaun's, it was all over the paper, guy spent some time in the hosp.
From the books that I have read, there is a lot of importance in knowing every nook and cranny of your hunting territory as well as the animal that you are hunting. So scouting as much as possible, just walking the land, will give you a good idea of what's around the corner or what's on the other side of a hill. Which can be very beneficial.
Making your own maps of human and deer trails, and different types of foliage such as group of pines,...