If you wish to perform adjustments on your CCM 450 DS then it will always be a good idea to possess a Workshop Manual to use as reference in case you want to know simple methods to strip off a certain part much like the Drive Shaft and fit it again successfully.
CCM 450 DS Workshop Manuals gives you certain diagnostic details for the automobile therefore if something is not working it helps you identify what the issue is and methods to correct it. You will be able to evaluate if this can be done yourself or that the job is just too big you can actually make a booking for your 450 DS in with a decent car garage.
CCM 450 DS manual