Get in touch with Virgel Umphenour, he is a guide here in the Interior. His son also guides in the Wood River area just south of Fairbanks. His phone number is 907-488-3885. I know lots of assistant guides here in Fairbanks, and a few guides, but Virgel is number one in my book. He is the only one I will recommend. Every once in a while you will see his name in one of the big hunting magazines, where he has taken in a party of journalist.
Often times there is Caribou in the local area of the Dall sheep, along with Grizzlies. So you might want to think about getting an extra tag. Often times at the airport I talk to sheep hunters, who had Grizzlies come into camp, or as they hiked down off the mountain ran into a herd of Caribou, with throphy class animals in it. So no matter what guide you get ask about the likely hood of running into other animals. Many times I have ran into Dall Sheep, while Caribou hunting. And Grizzlies are where you find them, everywhere.