I had to replace the lower mounts on both sides of my buggy - it isn't threaded, but it's a tight fit, and there is a roll pin that secures it and keeps it from coming out. With the help of some heat, some kroil , some elbow grease and the assistance of my coworker who is really good at such things, we were able to extract the pieces using a puller. In one instance we welded a nut to what was left and threaded the puller into that, and in the other instance it was broken off flush so we drilled and tapped a hole and threaded the puller into that.
I used some bolts that were on hand, they were a little long but had the right amount of non-threaded part to slide into the control arm. I just cut the heads off chamfered it slightly, threaded a nut onto the threaded end and hammered them in, and then drilled a hole through the bolt where the roll pin goes through and installed a new roll pin.
I'm not an engineer but I think they did it this way to keep the threads away from the shear-point of the connection to keep it stronger. (?) so I'm not sure I would want to drill and tap it.
I also did the drill-through and through-bolt treatment to the top mounts. No before pictures though...
