As I mentioned, I have not done the trip up to Grangeville yet, just been considering it and doing a little plotting in EVTripplanner. I have, however, done Boise to McCall and back without needing charging.Spend the night at the Super 8 and leave with a full battery to Boise. 200 miles. Looks like a couple of 14-50s in McCall if I need them. Shore Lodge and the Campground. @Rocky_H looks like you have done this in you S85. At least the Boise/Grangeville leg. Any insight is appreciated! Thanks.
And as you mentioned, there are 14-50 spots at a few points along the way that can be fallback points if things are looking iffy.