A) get the extra insurance on the rental car
B) get the extra insurance on the replacement rental car
...you find yourself wondering about whether the wife checked the correct insurance boxes while traveling a 75ft-wide logging road (and using ALL of it) made of 3-5inch riprap at 70mph+...and there's an F350dually coming the opposite way doing the same thing...
C) bring extra batteries and memory for the camera
D) bring twice the amount of camera memory that "extra" usually means
Everything is a minimum of 2 hours away. 2 hours in the land of no speed limits is 200 miles and a quick stop for coffee and beer.
Do the Going-To-The-Sun-Road. EVERYONE NEEDS TO SEE IT and the Grand Canyon at leat once in their lives! We drove it (several times actually) rather leisurely, stopping quite frequently. Go early, go early, go early. There are older (freshly rebuilt) touristy bus-type things that take groups on tours. I'm almost sorry we didn't take one just for the local guide knowledge. They have canvas soft-tops so you can look out in nice weather. The weather higher up in June was absolutely beautiful. It was rather hot (80-85?) in the flatlands, and a perfect 55-65F at the summit most days. July or August will probably be the same. There was snow on the roadsides. There's a small pond behind the visitors' center at Logan Pass. It's well worth the easy 1.5? mi. walk to the overlook. Go early, or you won't get a spot in the lot. If it's cloudy(raining) when you leave it will most likely be beautiful and empty of tourists when you get there. I didn't fish the pond, but others were walking in w/ fly and spin gear. I have seen a TV show called "Angling America's Parks" or something similar since and they did well in the pond w/ fly rods. The goats are stinky and have fleas. Chances are they'll want to share your shade; let them have it all. The sheep have attitudes and we watched them back traffic up some 15+miles into the valley for about 20-30 minutes. They stood in front of a honking driver (w/ NY plates!). Rodents will steal your lunch. Don't encourage them.
We stayed in the cabins on Lake MacDonald for almost a week. The old lodges were all really interesting, and serve alcohol. The meals aren't awful. The scenery from any of the dining rooms is spectacular. Lake MacDonald has lake trout fishing (and boat rentals), but my lake trout experiences all involved spinning gear so we didn't bother. None of the rooms we stayed in inside the park had AC. Just hang outside and enjoy the sunset and cocktails until it cools off. You meet some really interesting people! There is a catch+release area at the outlet to MacDonald Lake. I suspect it is bull trout spawning grounds or something, as they make a big deal about it. Didn't fish it.
Apgar Village was really pretty touristy (giftshops and ice cream). I wouldn't bother unless you need to give the kids a break.
Bowman Lake was really pretty. The campgrounds were pretty nice (pit toilets). Water is supplied, but I don't remember there being showers. We swam there. Nice place to spend the day. There were people fishing, but we didn't bother. A float tube would work well here. No boat rentals that I can remember. The road from Bowman Lake to Polebridge is 10-15mph singletrack, w/ cars headed at you. An accident in this area means a helicopter, or an uncomfortable 1+hour ride to the nearest paved road.Lots of bear scat in the trails. Hippies at the Polebridge merchantile make a good cinnamon bun. Coffee left a little to be desired, but considering I didn't expect to find any...
Trail Of The Cedars is a <1mile easy loop in a 300?yr old cedar rain forest. I would consider this a don't-miss. We did it after spending the morning walking trails at the summit. Wow, what a difference! You probably want to see if fishing is permitted in this section. It's just such a pretty spot w/ waterfalls and plunge pools. I would thik a 2-3wt, no more than a 4wt would be perfect. We did see fish when we walked this.
We spent most of our time on the west side, as do most tourists. Many Glacier and St Mary are on the east side and the flora is very different. It's worth a stop in St Mary for lake pics, and to check out how much the landscape differs because all the moisture dumps on the west side of the Divide. The Mexican restaurant there was marginal. Beer was cold tho'.
I regret not hiking/backpacking/fishing more, but I was recovering from a back injury. If you can, plan a day (or more) on The Garden Wall. You can see it from Logan Pass visitors' center. No fishing up there, but the short section I did was absolutely spectacular.
We did almost all of our fishing near family just northwest of Glacier (in Eureka). Apparently fishing inside the park is very spotty as the predominately glacier/snow-fed streams and lakes hold very little nutrients. That being said, my worst day of fishing inside the park was about equal to a fair day in NJ (qty- and size-wise). Honestly I would not have cared in the least if I caught nothing more than my first (10inch) westslope cutthroat in a little 50 x 100ft farm pond. Big-water wise you'll probably want to fish the Flathead. There is a fly shop (of sorts) at the southeast entrance to Glacier
Fly Fishing Montana in Glacier National Park
This is NOT a recommendation, only advising that they are in a high-traffic spot and easily accessible.
Check out the Amish general store in the Libby area (south end of Lake Koocanusa) for family style all you can eat dinner under gaslight. They had turkey w/ all the fixin's, and 4 different pies w/ 2 different ice creams (all made from ingredients grown on their farms). Please leave your beer and wine at home. You'll need to ask a local about this well-kept secret.
Additionally Lake Koocanusa has a bottom-release tailwater. I think it gave up the state record rainbow a few years ago. The same river (I think) that fills the lake fishes well up into Ferny, BC. Family took the 2 hour? drive up that way and did a guided float trip. They were quite happy w/ the trip.
The Tobacco Valley has the Stillwater River running along Rt93. It's easily accessible, and has every kind of fish imaginable, and lots of them.
All the really famous trouty water (like in the movie) is concentrated in the lower end of the state (8hours south?). Get over it, and enjoy Glacier NP. Fishing will be a bonus, if you have time. I'll try to find some pics and pm you a link in a few days.
hth-