Posted by DTM from response on rec.car.audio: DTM, you are in luck, the you can put a really nice system in your truck without ANY modifications. MB Quart 6.5" speakers will fit in the front doors, and MB Quart 5.25" speakers will fit in the rear doors, both are drop-in replacements and require zero modifications. I recommend the QM1216KX and QM1213KX if you don't plan on running a separate amp, and a QM160.03KX and QM130.03KX if you do. I really suggest you change the factory headunit (radio) to a aftermarket unit of your choice, its possible to retain the original deck but, a new headunit is the first step towards effectively upgrading the sound quality of your truck. Any D.I.N. size radio is a direct fit. We do a system for Benzel-Busch (M.B. dealer) that works out very well, it consists of a Alpine headunit (and CD changer?) of the customers choice, a set of the QM160.03KX and QM130.03KX speakers, a Rockford Fosgate 360.6 six channel amp powering the front and rear speakers as well as a SubSolutions sub (11"x11"x10") that we place in the rear cargo area. The amplifer fits under the rear seat and does not impede the movement of the seat at all. We have done systems in the ML320 both more and less elaborate than this, you can contact me directly if you'd like at 201-569-9079. glenn. S-WORKS M2 XTR grouppe White Brothers SC-70 fork