[sam's 72]

Seanh71,
I hope I got to you soon! I just read your post, there is not a nut holding the rubber line to the braket, it is a clip, ( it might be too dirty to tell that it is a clip ) but get a screw driver and tap the clip off with a hammer and the screw driver, once you have the clip out, the line will be sitting in the bracket loose, take some wire cutters ( Dikes ) and just cut the steel line, you are going to have to replace it any ways, Cut the line as close to the bracket as you can get, then just pull the hose out the bracket. Then get a new steel brake line, it runs on top of the A frame and is clamped in the A frame, just cut it as close to that clap as you can get on front and back side, ( the bolt is almost impossible to get too ) the brake line runs over to the drive side under the truck where it tee's into a brass block, take it off there, replace steel line, when you get your new caliper, it will come with a new hose, and good bleeder, install it, run the hose back into the bracket, and reclip it, then finish it up from there. I just got finished doing this on mine, the front is the easest to do. GOOD LUCK! If you need any thing else let us know.
Sam