1983 240D neutral safety switch replacement with lots of pics!
 

I haven't seen a newer how to on this for awhile, let alone one with pics. I just changed out a faulty neutral safety switch with a brand new one I got from PeachParts. Here is the process I followed:
Raise up the front end using a jack stand on the driver side frame, or use ramps.https://cimg8.ibsrv.net/gimg/www.mbw...df59e96bdb.jpg

Car up on jack stand.
https://cimg8.ibsrv.net/gimg/www.mbw...2d1a0692f9.jpg

Use a small flat head screw driver to pry plug loose. Work it off very gently, going back and forth from bottom to top.
https://cimg6.ibsrv.net/gimg/www.mbw...211624af1d.jpg

After the plug is off, spray with electric parts cleaner and use a nylon brush to clean out all the female contacts.
https://cimg4.ibsrv.net/gimg/www.mbw...12fe8c70df.jpg

Use a 10mm wrench and socket to loosen and remove the nut and screw that holds the shift linkage on. It's kind of a pain to get the socket on.
https://cimg4.ibsrv.net/gimg/www.mbw...40fa046f52.jpg

Use a flat head screwdriver and a wrench to pry and wiggle the linkage off. The linkage must be completely removed for the switch to come off. Be careful not to bend the tabs on the linkage.
https://cimg7.ibsrv.net/gimg/www.mbw...5ba25e7b13.jpg

Use an 8mm wrench to remove the two screws that mount the switch to the transmission. A ratcheting wrench works best as it's pretty tight.
https://cimg2.ibsrv.net/gimg/www.mbw...6ef5d66f48.jpg

Use more electric parts cleaner and a brush to clean where the switch was. Wipe it all with a rag or shop towel.
https://cimg7.ibsrv.net/gimg/www.mbw...6f2c0bc1bc.jpg

The old switch compared to the new one.
https://cimg7.ibsrv.net/gimg/www.mbw...bc84aabe1b.jpg

The hardware was pretty caked with crud so I used some carb cleaner and a wire brush to clean it up. This is before.
https://cimg9.ibsrv.net/gimg/www.mbw...87ea94daee.jpg

And after cleaning.
https://cimg2.ibsrv.net/gimg/www.mbw...7b59594211.jpg

I used some thread locker to keep the hardware from backing out or shaking loose.
https://cimg9.ibsrv.net/gimg/www.mbw...a527ff3fc4.jpg

Now reinstall in reverse.
https://cimg0.ibsrv.net/gimg/www.mbw...2bfd25398f.jpg

Make sure to use some dielectric grease on the plug contacts to keep the crud out.
https://cimg5.ibsrv.net/gimg/www.mbw...379353c6a2.jpg

Use a flat head or needle nose pliers to spin the plastic ring in the new switch to match up with the little tabs on the linkage. Push the linkage back on the shaft and reinstall the screw and nut. Don't over tighten! Push the greased plug back on, and viola' all done.
Lower the car and test to see if the new switch works.
Hope this helps y'all out. The illustrated how to's are few and far between, and YouTube comes up short.