I went to Glacier last year and was planning to do a brewery tour in Missoula, but didn't end up having time. Maybe you'll have better luck! Here was my original plan:
1) Big Sky Brewing (5417 Trumpeter Way, 11 AM - 5 PM, tours 3 PM)
2) Draught Works (915 Toole Ave, 12 - 9 PM)
- 7 min walk to:
3) Imagine Nation (1151 W Broadway St)
- 14 min walk to:
4) Tamarack Brewing (231 W Frong St)
Next door:
5) Late Lunch? - Notorious PIG (247 West Front Street)
- 11 min walk to:
6) Kettle House Brewing (Southside) (602 Myrtle St, 12 - 9:30 PM)
Can park centrally in one of downtown lots (West Front/Broadway)
I did end up visiting a few breweries closer to the park, but nothing really stands out to me now. Great Northern seemed to be one of the large ones in that area, but I wasn't a big fans of the beers. Coincidentally, I did end up meeting a brewer back at the lodge bar, however. He was in the area for a brewfest. He impressed me enough that I want to come back just to visit the brewery: