manual don't say jack, but, this is my advice...
carefully protect area from shavings... take a dremel tool (or regular drill with a dremel wheel) and cut grooves in the top part of the bolt. The idea being is that you can then remove the bolt with a flat-head screwdriver (or make an X and use a philips head).
That's my best advice... I had to do something similar for a worn down security bolt (you screw on but not off)