how I removed a broken body bushing bolt
So I managed to remove 7 of the 8 body bolts on my 69 I'm restoring, but I did break the one that is under the drivers door. I thought I'd post this here for my friends as I had to think how to go about doing this and while some posts talked about cutting the floor from above I could not find any pictures to show exactly how. So this is how I did it. I marked it out and cut the U-shape hole in the floor staying away from the factory plug welds holding the floor to the floor-brace and bent it back. Next I squared off the top of the 7/6"-14 bolt sticking out, so that I could drill a hole through the center. The hole will allow for the material to move a little due to thermal expansion and contraction during/after welding, hopefully moving enough to help break free the rusted threads. Cleaned up the threads and threaded the 7/16"-14 nut all the way down, and backed off about 1/2 turn to allow for wiggling the bolt down/up. Once I got a good ground on the workpiece I welded the nut in place. Then I started with an open end wrench wiggling the bolt up/down a little at a time each time moving farther and farther, spraying penetrating oil down into the threads to help. After about 3 minutes of this BINGO ! Worked like a charm I hope this helps someone down the line.