How do I take this out?

My fix for a broken seat track stud has been to drill the center where its broken off, and tap with the same size threads as the original stud. Then take a grade 8 bolt of the same thread size. (I think seat tracks are 1/4-20 thread, but its been a long time since i repaired one). Cut off the bolt shank keeping just the stud portion. Thread the stud portion in , and weld it at the top where the original stud head is.