> 
> While removing a very rusted exhaust pipe I have broken one of the bolts
with
> only a very small part of it still sticking out. What are my prospects?
> Drill?
> Heat?
> Removing the Head?

It happened to me two months ago.   The mechanic took out the engine. 
Removed the head.    He was able to drill into the bolt and use an
extractor to remove the broken stud.  However, he said that it was unusual
to pull out a broken  VW head stud that way but as there was no corrosion
on the bolt or in the cylinder block it was worth a try.

Jack Newton

89 Transporter (Safari Camper)