I just reread the post -- SELL IT.
Why do that -- This thing can become a member of the family.
I spent all of my school days driving 108s -- the first one was not as nice as the one you have now.
They really are great cars -- I know that this brake thing is not fun -- but it is very very rare -- I have not ever seen it in a 108 MB -- that is why I would like to know what the outcome is.
Once you get them setup they are great -- you must change the oil and you must lube it - other than that it is very forgiving.
If you do sell it PM me