I just had to deal with trying to get the stripped out screw out of my master cylinder- I wound up *
carefully* using my Dremel with a cutoff wheel to cut a slot in the top of the screw head. I used one of the wheels I had ground down already so as to not damage the reservoir cap. Then I used a standard flat head screw driver and the offending screw came right out. A trip to Home Depot for some new screws, and everything is copacetic.