Well I own the same engine and it can be difficult to take engine apart and can be easily damaged especially the draw bar and when dissembled the drive train and gear box and shaft assembly and removal could break something if you don't know what your doing! if it is a board problem the ps 2 3 volt board can sometimes be repaired, and or replaced with a ps 3/2 board!
Where do you live I'm in New Jersey !
Alan