I am not familiar with forest service ranger cabin rentals.
I would say that you should obtain some of the fishing guides from Montana such as Fly Fishing Montana by Brian and Jenny Grossenbacher and find out where you want to fish.
Then, fihd out how accessible the places are for fishing by walking or by boat.
Be mindfull of run off times as you don’t want to be there when the water is so high that you can’t fish.
I did a trip to Montana last year in July and had a great time and caught lots of big fish. We camped everywhere except of 3 nights when we stayed in motels to wash clothes, get cleaned up, etc. One of those nights was because a big storm soaked everything we had and we needed to dry out.
Montana is dotted with Fish Access sites. Most of these have access to the river and a great many of them have camp sites that are about $7.00 a night. First come first serve. These are somewhat primitive sites – pit toilets and most do not have water so you need to plan on bring containers to haul water. Most also do not have garbage service. As far as camp sites, they are very acceptable and some have nice boat launches. Contact the Montana Fish, Wildlife and Parks in Helena for a field guide.
Also contact Travel Montana, Department of Commerce for their vacation planner 800-847-4868 or their web site at www.visitmt.com
As for camping, we didn’t find a lot of privately owned camp grounds other tha KOA and their camp areas can vary a lot. Dillon has a pretty good one, Butte’s was horrible. However, they do have showers. Most campgrounds nowdays are really set up for RV type travelers and some don’t want tent campers.
AS for fishing, there are a hell of lot of places to go. The best fishing I found required a boat – and I did take my drift boat along to use. I also hired a guide on the Big Horn River (OtterCreek Outfitters) and on the Missouri – I can’t remember the guides name or who I booked him through – although he was an excellent guide. By the way, we fished out of Craig, Montana for the Missouri part of the trip.
In most places, you need to do a l ittle planning because there usually are not any grocery stores near where you will be camping and fishing. However, if you scrounge around, you can usually find everything you need. For example, the fly shop may also have beer, soda, milk – some shops can make your lunch for you, etc.
Good luck, If I can be of any more help, let me know.
Montana is a big state, the roads are good, the people super nice. You can get from one place to another pretty fast as the speed limits are quite high and I don’t think they really care how fast you drive or if you kill yourself doing it. I would suggest you settle on one or two areas to concentrate on and really explore them completely. Our biggest problem was that there was so much to see and so many places we wanted to fish that I felt conflicted.
Hope you have a good trip – I plan on being back there again next season.
If you have a little pontoon boat, or a bigger type raft, then I would suggest t hat you use it and just pay for someone to shuttle your car. You have lots of options for how long you drift – anywhere from a few miles to 20 miles.
Sorry for the rambling answer.