Greazzer, most of the info you need is in these two threads.
When I did my 85 300D, it wasn`t too bad of a job. being a Calif car, no rusty bolts to contend with.
You won`t need a spring compressor for the rear springs. remove the shocks, , then remove the calipers and hang them up on the sway bar. disconnect the sway bar links. then with a jack under the Diff, remove the 4 13mm bolts. lower the diff down and the springs will fall out.
I will say, if you pull some trailing arms off a parts car or one in the yards, do not cut the brake cables. I did, and when installing the PNP one`s, I then had to figure out how to remove and install the one`s off my old arms. just take them apart where the two meet under the car from the wheels.
reading through the various Sub Frame, Trailing Arm threads, seems like the job is harder and maybe more confusing that when actually getting in and do it.
Just make sure the car is well secured and safely jacked up. after the sub frame is dropped, there is nothing but the jack stands holding up the rear of the car. when I had mine out and looking under there, it gave me the willys thinking, all this thing has to do is move/roll back etc... and Iam dead.
BE SAFE!!!!!
Charlie.