John, That is a point that I did not include. On older instruments where the arm for the crows foot (the arm from the bottom of the C key to the crows foot) is thin compared to todays it could have been taken out of whack more easily than (most of) todays clarinets. Look at a modern Buffet and compare it to a 1940s Buffet as the thickness difference is large. to "un whack" it I push down on the C touch and use a thick screwdriver as a base for the crows foot to be pushed against. But more than likely the curve of the crow's foot arm is incorrect and that needs adjustment too. Bending the spatula touches is another option but I tend to want to keep all the angles of things intact and level with each other. Truthfully, I don't have the time constraints of a music store dealing with rentals so I can be a bit more picky.