Refinishing 1950's GE metal Kitchen Cabinets?

We are trying to refinish some 1950's GE kitchen cabinets which still have the original enamel finish in pale yellow.  Several of the doors are chipped or blemished and several have surface rust resulting from their being stored outside before we rescued them 10 years ago.

Our local auto body shop is trying to respray one of the doors ussing standard auto finishing techiniques (not sure of the exact process) and they are having problems with the orginal finish "plating" or "blading" through the new paint.   They are going to start over using an etching primer and then re-spray.

Does anyone have any experience with this?