If changing, suggest you install foam baffles behind the front 4" speakers. Make a huge difference in the quality of sound from the speakers. I used XTC foam baffles available from Crutchfield: Car Stereo, Speakers, Home Theater, LCD TV, Digital Cameras and paid something like $6.00 for them.

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My 1988 Mercedes-Benz 560SL Photos by RE_Rick_Williams | Photobucket