I recently acquired an '86 190d 2.5 5spd. I made an attempt to swap out my old fan clutch for a new one over the weekend. I used an 8mm allen head socket and breaker bar putting force in a counter clockwise rotation (this is a right hand threaded bolt right?) and did nothing but strip out the recessed allen bolt. I read some tips in an earlier post and would love to know which method is best for removing the stripped bolt.

I have a mig welder and could weld a bar to the bolt head to remove it - is this the easiest way - are there any precautions I need to heed before I start welding to prevent frying all of the engine electronics?

What about the jb weld an 8mm allen socket or similar sized torx socket into the stripped bolt head technique - does this really work?

Any engineering geniuses out there got a better technique for me to try?