I don't want to pour cold water on your plans however .
We live in the tourist west coast, given what happened last year I would leave it till the foreign holidays start again, the scenery will still be there and the infrastructure will be improved by them.
Highland council are encouraging aires and more tourist infrastructure will be in place with less folk.
There will this year be more rangers to help police the tourists but the Police are really thin on the ground up here, proportional to normal population not the many times inflated tourist season.
If you still want to then either find a different route in Scotland and book campsites, Free camping could be stressful finding a place, I looked last night on Scottish motorhome campers FB page Map of free camping spots, I know locally that very many of those are gone, fenced off or boulders in place to prevent there use.