DO NOT go to all the hassle of grinding the rivots. That way to much extra work. You'll need an 1 and 1/8" 1/2" drive socket, a 1/2" rachet/breaker bar, jack stands, floor jack and a come-a-long, oh and some chain. Raise and support vehicle on jack stands on the frame +/- 6" behind radius crossmember.Doing one side at a time, Attach come a long to frame and outer portion of axle w/chain. Support axle on that side w/ floor jack. Remove radius arm bushing nut/washer and outer bushing. Tighten come a long until arm comes out of bracket. Replace bushing and release come a long. You may need to hammer radius arm sideways to line up again. You may also need to come a long the opposite direction. install rest of new bushing componets and nut/washer, torque as necessary. Repeat for other side.
I just replaced my axle pivot bushings, radius arm bushings, springs and spacers, packed the wheel bearings, and sway bar bushings on my wifes explorer, it took me about 6 hours. It actually took longer cause I cleaned and painted everything, more like 10.
Hope this helps. Rob
After writting all this I looked at your year vehicle, not sure if its the same or not. I'll go research it.
After rereading your post I reallized its your 94 ex not your 06 truck, so its exactly the same