The right drive shaft?

I have to change the drive shaft in front right, because it has a noticeable play. Now I have ordered a drive shaft on ebay, Now I am not quite sure if I can install it in my A8 4.2 vintage 95. The purchased shaft has code 4D0 407 272 L with year 96, the current code 4D0 407 272 J with year 94. The purchased is also about two cm longer. Does anyone know if this is the right wave for my AluV8 or if the letters are not important at the end? The flange where the drive shaft is screwed to the gearbox, has also played, is there a camp gone? if yes, can this be changed relatively easily? If someone knows something about it, I am very grateful to an answer, I have already Googled you find nothing.
Other question: Is the cable "USB OBD2 KKL Interface" from carscantool on ebay usable for diagnosis on the A8?