Bought a used GS, Corbin seats. The cap head allen bolt that holds the backrest in the seat was stripped out and frozen in place when I got it. I soaked it w/ penetrating oil, drilled it, put in an EZ out, and the EZ out snapped off flush with the bottom of the allen socket in the head. 4 brand new titanium drill bits have met their maker trying to re-drill the bolt. Is nothing harder than EZ-out? I've been drilling slow w/ oil on the bit. Nothing works. There's no way to grasp the head. It's recessed in foam, and rounded off (BRILLIANT!). All I can figure is find somebody w/ a stick welder, lay a nut on top of it, and use a thin electrode to weld it to the bolt at the inside of the nut hole. It's only a 1/4-20 bolt, so that's a SMALL electrode. I also am "friend with welder"-less. Anybody got a miracle idea for me?