thanks for that. the input shaft has these squared dogs but unfortunately they don't seem to have the problem. the problem is on the output shaft where the dogs are oval shaped so the machining trick as per link won't work. what will work possibly is to skim the top off the protruding oval dogs rather like lopping the head off a poppy.
thats all i can think of?
if anyone was needing the input shaft cogs doing though i'm sure it would be a good start!
regards
Taffy