If you could pick one spot on the Gallatin River...

[NCTroutFinder]

Hello everyone! I wanted to reach out to see if you all had any suggestions about fishing the Gallatin River in September. My father, brother and I have made our fly fishing dream come true and we will be spending a week in West Yellowstone. Each of us are doing our own research on a different river to fish. My choice is the Gallatin. My question is, if you had to pick one spot to fish there, where would it be? My father has been talking about doing this for years now, and my brother and I want to make it the best trip possible for him. (this will be the first time to Montana for all of us.) It would be a bummer if I mapped out sections to go to and it ending up being the worst place to fish on the river! Since traveling up and down HWY 191 is probably not what we want to do, I was thinking of finding a good stretch of a few miles to spend the day on. I've read, in general, that the best areas are the Upper and the Canyon sections. Now I ask, where to go in these sections. Any advice will be greatly appreciative. Thanks so much for your time, and I can't wait to get into the Montana waters!