The latest in w123 ball joint tools
 

Yes, for pressing the big one in...

This is 2015 edition...

Of course there are threads about the HF one, and the Autozone tools. I think that SIR makes a good one...

But what about the eBay ones.

Here is one from Germany (China, I'm sure). Does it ship from Berlin to give legitimacy??

Mercedes Benz Master Ball Joint Press C Clamp Repair Remover Installer Tool | eBay

This one has a few more parts and is a "master" kit....

http://www.ebay.com/itm/Mercedes-Benz-Master-Ball-Joint-Press-C-Clamp-Repair-Remover-Installer-Tool-/311492805269

Anyone tried any of these or have a reason to think that they wouldn't work for installing the big ball joint into the knuckle on a w123?

On the first one I have always wondered if there is something in the kit that would work on a W123?

C-Clamp press tool forged (not cast) form SCM440 Steel (HRC 38-42 hardness).
.Front Suspension Ball Joint press fixtures for W220 / W211 / W230 / W215 / W219 Chassis – used in Conjunction with the C-Clamp Press.
.Front Sway Bar Ball Joint (pressed into control arm) press fixtures for W220 / W211 / W219 – used in Conjunction with the C-Clamp Press.
.Front & Rear Suspension Ball Joint press fixtures for W163 / W164 Chassis – used in Conjunction with the C-Clamp Press.
.Ball joint socket (4-prong 3/4"Dr) for servicing front & rear ball joint on W163 / W164 Chassis.
.Applicable: W211, W163, W164, W215, (W)R230, W220, W219.

So,

I'd be willing to try as a Guinea pig... But I don't have a car apart, so I don't know what I'd be looking at to see if anything is useful..,

On this one, in the comments, someone said they were able to use it on a 190e. Has anyone done an analysis of the sizing of various press in ball joints from newer cars to see if there is size consistency?

http://smile.amazon.com/gp/aw/d/B00061SGJ0#Ask