I removed mine on my '86 300E by sliding it out towards the rear of the car at an angle. It was a little tight but not difficult. My car is stock but if you have modifications to the rear shelf e.g. additional speakers or other equipment it may interfere.

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'86 300E 5 speed
'71 Triumph TR6
'46 Cushman Scooter
'41 Ford 9N tractor