RJK:

The bolts should be tight, but not that tight, so I'm guessing they have just become frozen with rust and corrosion, like most old bolts that are seldom touched. Try generous applications of a liquid wrench-style of penetrating oil, let it sit a bit, douse it again, and whack the end of the bolt with a hammer to jar the crust loose.

By the way, search this site for tons of info on changing out these bushings. You will save yourself much time and grief.

230/8