I replaced the struts on my 87 300TD today. I had to use 3 chisels (progresively larger in size) to remove the pins from the back 2 hinges (+ WD40 of course). Most importantly, put these pins in first when installing the new struts, or else you will never line them up. The pins inside the car are much easier to line up.
I received 2 different brand struts from Febi and Stabilus. Stabilus looked exactly like the OEM, but they both fit.

1987 300D 186Km
1987 300TD 196Km
2001 CLK 430 Convertible 32Km