1985 300D, 1991 560SEL
M10 x 1.5, but do not have the shank length at my finger tips.
If you get stuck, let me know. I'm sure I saved all the hardware from when I swapped shocks a few years back, but it would be up at the airport, and I don't go there regularly any more.
I've located a set of caliper bolts and the shock nut through my local MB store. Thanks to @liviu165 for the proper part number on the bolts. The number I had for them was showing $40/each! I'll have to order the parts this afternoon and will have them some time next week.
Ugh. Waiting sucks.