Acheson emerged victorious on the 37th hole against Alan, who had set the pace with a blistering start and pushed the match all the way with his determination to keep going.
Spectators were treated to a tense and high-quality contest as the pair could not be separated over the regulation 36 holes.
In the other final, Alisdair secured victory on the 18th against Davie in another closely fought match, rounding off a finals day that showcased the depth of talent at the Largs club.
Club officials praised all the players for their efforts and paid tribute to the many members and supporters who turned out to watch and encourage the finalists throughout the day.