hi there recently given a puch magnum xk not sure if 78 or 79, how to tell? I was going to sell it but now my son wants to work on it with me and I dont know the first thing about vintage mopeds. Can anyone send me a pic of how the rear brake is routed and put together, also I know it needs couple chains, any idea where to get them? Does any of the major auto chains carry moped parts?