I guess this will be a predominantly low level route?
Many years ago, inspired by the antics of Ian Leighton (Holmfirth) & Robin Price (C-le-M), as reported in several editions of the FRM; I indulged in a mega session of map fondling and traced the N section of the W coast of Scotland watershed from Laggan Lochs on the Caledonian Canal to Cape Wrath. It followed some amazing ridges and evocative summits. The main problem was the logistics of re-supply, as even the few road-Xs were all miles from any communities that might have provided opportunities for shopping / re-supply. It would have required a week's tour in the car, burying food stashes.