The 1996 has the old cable operated release for the shifter like the W124 E320 had. Pop the wooden trim from the console and see what is not letting go. it also will have another cable leading to the ignition switch which releases the tumbler to go to full release position to extract the key.


http://mbworld.org/forums/e-class-w210/316922-help-shifter-stuck-park-2.html

You can see some pictures of the problem in the link above.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)