The panoramic roof will fit any SL from 1990-2002, but it may need adjusting to fit correctly. Full instructions are on the WIS CD or you can get a dealer to do it. Mercedes do not suggest alternating between the two, unless adjusted each time.
I'm inclined to agree with Stuart. However, when the Panorama was introduced M-B sent a service bulletin to it's dealers stating that the top could be retrofitted to cars dating back to 1992. At any rate, you definitely would have to change the seals, since these were modified significantly in 1994.
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