Missoula, MT to Helena, MT questions

[DubyaGee]

A friend and I are trying to plan a 2-3 day bike ride from Bonner-West Riverside, MT (Missoula) to Helena, MT. We were trying to decide whether we would ride un-supported or supported. I've driven this route before, and there didn't appear to be much in the way of accommodations after Ovanda. If we ride supported, we were wondering if there were places to camp where our support crew could park a vehicle and setup camp? If we ride un-supported, we were curious about places to camp (stealth?),minus the vehicle, and places to get water along our route?  We would appreciate any other recommendations from folks that have ridden this route.

Thanks

This is a link to our tenative route: https://goo.gl/maps/lyl8I

Possible alternative route: https://goo.gl/maps/AevUQ