NSEU,
No worries - I have appreciated your inputs in the past. And, as I said before: Your thoughts got me thinking.
I must admit that I havn^t fully understood yet how this thing works. On the output / wiper shaft there must be the trick with the cams, looking at the (single) figure in the CMM.
But I am afraid only by looking at the CMM, I won^t get behind the secret. Maybe I^ll run into a B747 wiper expert some time...
Happy Landings,
J.V.