Peter,
Thanks for the reply.
Who could tell me if the engine would run upside down for any length of time...or on its side? I am guessing that as long as fuel is being delivered, the heart will beat? Yes, that would depress the bearings, wouldn't it? Literally.
I gave MB North America a call...the fellow I spoke to didn't know.
I'll call again, try again.

The prudent thing to do, I suppose is to tear-down the motor completely, pressure test it or magnaflux it, and go from there. To do otherwise may be inviting another breakdown some miles down the road.

I didn't know cars had rollover switches...I cannot recall reviewing a part on this motor/injection pump or anywhere else that has that function.