The %^!$@! Shackle Bushing Outer Shells

The shackle bushings consist of two concentric metal cylinders with rubber between them.  The inner shell and the rubber comes out easily, but the outer shell seems like it's welded into the frame hanger.  Here's a picture (the offending piece is the thin ring around the hole):

This has to come out or the new bushings won't fit.  After scouring the forums and getting through this myself, here's what seems to work best: Using a hacksaw, cut through the shell at two locations on opposite sides, and then use a chisel and hammer to push the two half-shells out.  If it doesn't come out with a few taps, it's probably because you didn't cut all the way through the shell -- even through it seems like you are sawing straight, the ends seem to cut faster than the middle.

Here's a bad way I found to do:  Use a 7/8-in step bit to clear a little bit of the shell on one end, and then a 7/8-in hole saw to drill the shell the rest of the way out.  It feels great to end that sucker with a power tool, but the problem is the resulting hole ends up a little larger than 7/8-in, probably because it is impossible to hold the drill exactly on-center during the excavation. So, I now have one shackle bushing which fits, but does not fit snug; it has a little play in it.  It seems OK otherwise, but in retrospect I would rather not have done this.