Gairloch to Applecross is an odd one as there is only an hour and a half between the two. 2/9 why not book the Cuillin Hills Hotel at Portree on Skye. You could leave Gairloch, follow the road round the coast through Kenmore to Applecross, go over the pass to Tornapress, then to Kyle of Lochalsh (fill up with fuel here, the middle two pumps sell super unleaded), take the Skye Bridge and then either do a clockwise loop of Skye turning left onto the a863, a850, a87, or follow the a87 past Portree to Uig, get on the a855 for 2 mins then take the single track road up and over the Quiraing before the a855 back to Portree.
Then the next day take the Armadale to Mallaig ferry and head back to Fort William from there, quick detour up to Spean Bridge to pay respects at the Commando Memorial then back down the A82 to North Ballachulish, ignore the bridge and hang a left onto the b863 to Kinlochleven aka ’the scotburgring“. Spits you out at Glencoe, get back on the A82 heading towards Tyndrum (The Real Food Cafe is a great lunch stop) but don’t miss the turning a few miles out of Glencoe to the right towards Loch Etive for the “skyfall” photo.
From Tyndrum, I’d stay on the A82 down to Tarbet, turn right onto the A83 and then come off on the b838 at Arrochar, take the rollercoaster coastal a814 until you reach the roundabout, turn left to stay on the a814 and then left at the next roundabout for the A817 aka “The Haul Road” - built to transport nuclear weapons over to Faslane submarine base, you can stop at the lay-by and see the base and any submarines that are in. Hot foot it over the A817 and you end up back on the A82 by Loch Lomond golf club. Then you’re a stone‘s throw from Glasgow with the choice to stay in Balloch at Queen of the Loch and explore the Trossachs and The Duke’s Pass the next day or just head home.