Well, as I wrote earlier in my first  attempt to work on a wasserboxer
(changing headgaskets on my "new" 87 Westi GL)   I encountered the dreaded
cylinder stuck to the head syndrome.  After much struggling and "tapping"
(read beating) with a plastic hammer per bentley, I gave up and removed the
cylinder and head as one unit.  Actually it is a good thing I did because it
turns out that I could have tapped on the head with the plastic hammer well
into the next  century with no results.  I actually spent over two hours
trying to part the two. My hammer size grew with my frustration so I ended up
getting the two apart with a sledge hammer and several strategically placed
blocks of wood.   To get the errant cylinder back into the case I ended up
cutting the handles off my ring compressor and clamping them with a pair of
needle nose vice grips.  It wasn't pretty, but it can be done...
Don Record