I had one stuck, seized threads were the culprit.
The head had to be removed so the GP could be drilled out.

Don't let GP's change your mind on buying one, though. By all means, E300's are the best of the IDI (non-CDI) diesels.
Do yourself a favor, look for a nice '98 or '99 turbo, and enjoy it!

__________________
99 E300 TD -- sold
01 540i 6 spd