Torsion bar end bushings

How exactly do you "split" the shells open on the torsion bar end bushings? I know the pivot bushings need to be drilled out near the 4 corners, is this the same method to split the shells on the end of the bars? I'm trying to skip having to drill the rivet out and my thinking is if I split the shells I can burn out the rest of the remaining bushing, slide the new bushing on, reclamp the shell and reweld it if I have to.

Thanks