Do your Mugen bushings have a steel sleeve around the bushing? The factory bushing is rubber formed around a steel sleeve, which when the rubber splits on the attachment points Resulting in removing the rear trailing arm assembly(bitch if you run into seized bolts)and pressing the bushing sleeve out on a press or possibly a B.F.Hammer .Use a large diameter tube or a old hub bearing race(thatas what i used) to press the old bushing out. same procedure to install just make sure the mount rod with the holes is positioned correctly so it will bolt up to the floor mount.. Hope this helps. JOE