I'm so close to finishing up my Tesch with MAVIC grupo; however the rear derailleur stop (the washer like thingie with a couple of tabs on it that fits between the derailleur pivot and the dropout and prevents the derailleur from swinging too far forward) is missing. Do any of you erstwhile classic bike dudes have one in your box of goodies? Merry Christmas from Wichita, Rodney Handsfield