hi @garry-cairns,
welcome to this forum, it is a very helpful place.
I have travelled around the northern highlands many times on my bike. I found the best way is, trawl internet find a load of routes and then use the excellent rout planner to make up the routes to suit your needs. the MRA route planner is a very good piece of kit, just be wary of some of the pitfalls, (read the forums) such as making sure via/waypoints/shapping points are correctly placed on the intended road of travel.
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