OK,I give.
How do you get that outer rear control arm bolt so I can replace the bad left rear control arm?
I'm almost afraid to ask.
DB444

 

I think you will need to give more information. Year and chassiewould be helpful (my 300D has a W123 or just called 123 chassie) as not all years and models of Control arems are the same.

And by getting Bolt out do you mean you cannot unscrew it or the Nut that holds it or do you mean it is stuck in the Arm (this happend to me with my Lower Control Arm) and cannot be driven out?

 

I'd think my 1983 240d is the same as your 300d.
I want to replace the left rear control arm.
I don't see a way to get to the nut,24mm wrench size,for the outboard swing arm bolt.
It's is beginning to look as if the differential and rear subframe would need to come out.
I may have bitten off more than I was hopeing to chew.
DB444

 

I looked some more and can now see the rear subframe needs to come down atleast some.
I'll work on that.
DB444

 

If the Left Rear is the Driverside Rear I have due to an accident replaced that one with a used one on my Car. However, that was close to 2 years ago and I cannot recall any special Problems.
I do remember I had to heat a Nut to get it loose.
I cannot go out and look at my Car today as my Wife has the Car and goes to College at night; I do not expect Her home till around 10pm.

In the mean time here are some of the repair links from another forum I am a member of (Diesel911 on that forum).

 

I've looked a lot more deeply into the control arm replacement issue.
The rear sub frame has to come down some to get at the outside bolt.
The rear coil spring must be compressed to releave the great pressure on the control arm.
That requires a special tool that costs $570 on-line.
Have not found it available for renting anywhere.
Found a Chinese copy for about $220 to the door.
I hate to buy a tool that expensive that I might use once or twice.
Looks like I have no choice.
DB444

 

I sent a PM to you.
For others: I have read that after you remove the Shock Absorber and you raise your Car up enought you can lower the Rear Trailing Arm enough to remove the Spring. I have not tried this and do not know the details.

Looks like I forgot to post the Repair Links;

If you fell that you need to compress the Rear Spring (NOTE:NOT strong enough for the Front Springs) live in the US and are near an Autozone they rent ones out like in the pic below for free; they refund you back the money when you return the tool.
I believe there is enought room for them.

 

I managed to compress the Rear Spring with cheapie Spring Compressors like the ones below but that spacing was difficult do to the fact of the Big Casting with th 2 hooks that is on one end. It would have been better if both ends had only 1 hook.

When I tied to used them on the Front Springs I bent up the Threaded Rod on them and ended up making a Spring Compressor just for the front.

See pic of cheapie tool.(This is not a pic of it being used on a Mercedes it is just to show the double hook casting.)