OK, the 1991 560SEL has been sitting for awhile awaiting a brake job. During that time, the car's finish is sooty from the exhaust from parking the 300DT next to it.

In addition, somehow some black grease or oil (can't tell which) ended up on parts of the hood. I'm thinking of trying Mother's polishing compound or the purple degreaser from Sam's club. This car has a very nice finish and is garage kept. I don't want to screw up the paint.......