1985 300D, 123 chassis.
Searching through the archives finds many opinions on this topic, most do not answer my question.
With over 200,000 miles on the clock, I am rebuilding the front suspension, and subframe bushings. While I have the proper coil spring compressor, it's best to go ahead and replace the rear trailing arm bushings.
The manuel states the entire rear assembly must be removed. My thought is, compress the springs, remove them, and lower each trailing arm. Use a large "C" clamp to press out/in new bushings, without removing the arms from the car.
Any thoughts? As far as I can tell, the arms are not rusted. Alan

Here is the post on my 300TD rear suspension rebuild.

300TD REAR suspension rebuild

The front end rebuild

300TD suspension rebuild progress

I did the rear trailing arms both ways, I left the right one in the car and took the left one completely out. I found that working on the trailing arm while still attached to be a royal PITA. It was a little more work to disconnect everything, but R+R the bushings on the workbench was a hell of a lot easier than in the small space available and under the car. I also degreased the arm painted it with POR15. Completely cleaned it up.
IIRC The only thing you have to do is release the parking brake cable. I did this at the adjuster unit and fed the cable through its eyelets.
Either way is doable.
While your back there look at the differential mount. Its easy to replace and it is a rubber mount for the rear suspension.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car