Thompson and co-driver Larry Higton, from Newton Mearns, finished 12th overall in the Mull Car Club event based at Dunoon Stadium with closed road stages around various locations of the Cowal peninsula.
As a result, they won Class 7 and were second two-wheel drive car home behind Irish champion Damian Toner out of the 79 finishers in a field which included many top international drivers in semi-works machinery.
In their two-litre AMD Ford Escort Mk2 Thompson, general manager at AMD Contract Services in Dumfries, and Higton were seeded at 23 in the 120-car field .
They got off to a steady start on the two short opening stages around Dunoon town centre before upping the pace out in the lanes to set 16th fastest time on the final stage of Friday night to maintain their 23rd position overnight.
The Saturday saw two loops of four stages and the pair continued their good form with top 20 stage times in the morning to move up to 13th overall before moving up the leaderboard in the afternoon stages to set some impressive times which culminated in a superb 12th place overall at the finish.