Don't know what size camper you are contemplating, but I would hate to try to drive one on some of the "neat" roads there. I've done it in a standard minivan (Toyota Sienna and Ford Galaxie/Windstar) and it was tight.

Our favorite UK travel plan is self-catering cottages. Spend a week in one location, make day trips all around, then move on to the next central spot. You always know where you are coming home to, so can take longer day trips without worrying about where you will bed down that night. Breakfast and dinner at "home," pub lunches or pack your own lunch if you wish. You can get by with a smaller car that way, lower fuel costs and able to poke around on the smallest of roads/tightest of little villages/easy to park!!

There are tons of resources online for self-catering rentals -- many portals are drawing from the same database of rentals and you'll recognize that quickly. www.slowtrav.com has reviews and referrals. We had good service from a company called (I think) Stillwell but not sure if they go into Scotland, IIRC seemed to specialize more in Cornwall.

I can post some more links if you're interested in this idea. Whatever you choose, have a great time!