replace thermostat on 1987 420 SEL

[RKreutzer]

Hi, everybody
I would like to replace the thermostat on my '87 420. I looked at the CD and the archives but could not find a good removal description. I can see the front and top bolts of the thermostat housing but not the 3rd in the rear. I have a hard time to imagine how to get that rear bolt out without removing pieces to the left. I assume the top radiator hose has to go and that will provide more access but it doesn't look like enough space. Is there a special wrench?
Do you get to it from below?
If anybody who has taken it out on a 420 could tell me if and how it can be done without removing other parts first, it would be appreciated.
Also, the archives are mentioning anti-seize compound when installing. Is there a lubricant like WD40 recommended for removal to avoid broken studs?

Thanks for your help.
Reinhard Kreutzer