I keep banging on about bike hike but it's really good for this sort of thing...you can toggle between two maps on the same page, one is a google map and the other is OS, so you can see footpaths and plot your route.
On the OS map you don't need massive navigational skill to see the steeper hills just look for contour lines close together, the closer they are, the steeper the hill, find a footpath and you're away.
Tbh I would go over to Edinburgh and run up the course, it's not that far?