Update:  I ended up having to drill four of the studs/bolts out.  I cannot
imagine doing this with the engine in the Westy.  I started with a very
small bit and then worked my way up to 1/4".  I also ended up getting a
helicoils kit because I could not imagine picking the threads out of the
holes I had drilled and even though I had four good holes with original
threads I drilled them out too and put helicoils in all eight holes.  I
figured I did not want to have to fight with exhaust studs or bolts
again.  BTW the waterpump came out realy easy.  I cleaned all the steel
engine coolant pipes and will POR 15 them.  Thanks for all the advice.  I
accumulated a few new tools for this job!

Pascal
84 Westy