Dartin for Divorce

In this application you'd be fine just redrilling the spring plate. I opted to run a nice thick universal spring plate sourced from a offroad fab shop. Either way, just make sure your ubolts are in good shape, Ive seen them rusted/pitted more than once.
Spring relocation kit. I'm not sure how much tire clearance your going to gain, the inner fender will be your limiting factor. You should be good to go running 245/60's with your current setup. I"m running 235/60's, I have the same wheels as you and perches are in the stock location. I could run a 245 if needed.
Your stock hard lines and Tee will probably work out, I would run a new rear brake hose. You could also order a set of lines up, or even build your own.