Clear coat or not???
 

Recently purchased a jet black low mileage '79 300 SD Turbo. On my first attempt to polish & wax, my pads filled with what appeared to be black paint! This never happened with any late model US cars I've detailed. Does anyone know if Mercedes used a clear coat topcoat in '78/79? How do I minimize the micro paint loss during polishing and waxing?

If you see black on your applicator, then the car does not have clear coated paint. The only way that you can eliminate this is to use a wax that has no cleaners in it. However you are not going to remove that much paint unless you are using something that has a fairly high abrasive level.