Joshol - you were absolutely right. The three bolts holding the box
onto the frame broke, allowing the box to hang down and come off the
steering column shaft. I took the box out and was able to get
the remainder of the bolts out with an easy out. I will check the frame
wall for cracks
According to a local Mercedes mechanic, this is not uncommon to these
cars, as you also have suggested, so other owners should take note
and torque the bolts occasionally. I'm thankful it wasn't more serious.