Hi, have a MIM jazz 4 banger and I am having problems with the pots cutting out when I move them. Would it be considered an upgrade to install American pups and pots or are the same as the MIM electronics in which case should I just have them cleaned? Also, should I get them from fender if it is better to change them out or would people selling American parts on eBay suffice? Anybody out there done this? I would like to keep it fender. Thanks