Barbara, Providing you can arrive Glasgow Buchannan Street Bus Station before 10:00am The Scottish Citylink coach departs at 10:00hrs arriving Fort William Bus Station at 13:08 and the wonderfully named Shiel Buses bus departs from same location at 13:25hrs. This information is according to both companies current time tables for May 2014.
You can even get off Citylink Bus at Corran Ferry and catch Shiel Bus there.
If doing this I strongly suggest you contact Shiel Buses beforehand to inform them. Board 13:45 ferry to Ardgour as a foot passenger and board bus on the ferry. Do not wait at bus stop as bus will likely shoot right past and onto ferry!
Hope this helps
Ian Shiel

If you get the 10am bus from Glasgow to Fort William you will be in time to get a bus to Acharacle. The other option is to get off at the Coran ferry and cross to get a bus to Acharacle.

Ian C.

I see Mr Shiel beat me to it.

Ian C.