Booster you are right. There is a nut under there and if I had the control arm off and a 19mm wrench with just the right offset it could probably be unbolted. With the control arm in the vehicle that is not going to happen.
Today I got medieval on the old bump stop plate with a hammer and cold chisel and managed to pry up one end of the plate and break off the tang that keeps it from rotating.
After a bit of sawzall action the half that was sticking up was cut off and I was able to shoot a little WD-40 through the slot at the threads. Some more hammer and chisel work got the remaining piece to rotate counter clockwise and then the threads let loose and I was able to unscrew it and fish the long nut out of the bottom with a magnet.
The battle scars were cleaned and hit with a shot of black rustoleum and it was ready for the Timbren.
The Timbren installed easily enough. The one catch is the mounting plate is angled so I made a mark of the high spot with a red wax pencil in order to make keeping it aligned easy. Here it is all installed and ready to go.
When I get the other one installed I'll measure to see if it raises the front end at all and come back with a report on the difference in ride.