[svr]

In my experience drilling and easy outs are successful maybe 1-2 times out of 10, you have to be able to drill straight in very near the middle of the bolt, rarely are you able to do that with success. I assume since your are near completion that the bolt broke because it was tightened beyond its ability to hold down. If it's one that is still in there from disassembly it's a different story. So assuming its in a clean hole it shouldn't be that tough to get out now that the head is off of it. If you can't get at it from the bottom you need a welder and somebody who has done this before. Lay something non flammable around the hole to protect the paint from splatter, use a flat washer the same size as the bolt right over the hole with a like sized nut right on top of that. I use a pair of old needle nose vise grips to hold the nut down tight and clamp the ground to the vise grips. A Mig welder works much better on these small bolts as the wire can reach down to the top of the bolt and get hooked on. It helps if you have somebody holding the vise grips tight so the welder can hit the hole with some accuracy. Fill up the nut with weld, doesn't take long. let it cool a bit and put a wrench on the nut and start working it back and forth slow and easy. Have had to repeat this process several times to get success but will work 9+ times out of 10. You may have a bit of scorched paint right around the hole but should be minimal as long as the flat washer and nut are held tight and flat. Best wishes, just my experience.