Are you asking what tool I used? Probably a cutoff wheel on the air grinder or electric grinder.
I hacked at them with a sawzall likely. I just sliced the vertical cuts and pounded the sheetmetal up out of the way. Crude, I know, but once I realized that my truck was going to rust out from underneath me eventually, cleanliness of cuts tends to go by the wayside. :(
They are bent 1/4" plate. A local fab shop cut the steel from plate and bent it at a right angle to my specs. I used cardboard and the old bracket piece to mock up what I wanted, then clamped the 2 brackets together (they are mirror images after all) and drilled the holes.
I belive this is the front bumper, but the concept is the same. Once I had everything mocked up in steel and tacked together, I hauled it off to a pro for final welding.
Absofeakinlutely. Admittedly my rear bumper is tied into the rollbar, but I swear you could grab the rear bumper with a crane and twirl the truck around like a toy. :D It's also important to note that I added that ginormous bolt that goes through the existing hole in the outer frame wall and through a hole I drilled in the inner frame wall. I've got very little confidence in the stock bumper bolts when it comes to yanking my butt out of the mud.
Oh, and kiss your tailgate goodbye unless you do it slightly different. :(