I initially tried doing the pinch-weld mod while leaving the tire on the Jeep, and using a hacksaw to cut the metal. After cutting one of the cuts, I said screw that, and went and bought some new metal blades for my Sawzall.
I wish i would have taken photos during the entire process, but I did not.
Here's a quick how-to on how I did mine. I run 265/70/17 on AEV Pintlers with no lift, and no rubbing - for reference.
1. Jack Jeep up, use jack-stands for safety - remove tire.
2. Use Dremel to cut plastic fender well lining. You want to cut the "lump" out of the fender well - you can't miss it, it's the part the tire rubs on. BE CAREFUL not to cut into the sensor behind the fender well plastic. Just pull the plastic outward as you cut it and you will be fine.
3. Be prepared for hot plastic when you cut the fender well plastic. I caught a couple extremely hot drips on my arm, and on my face while doing this. Be sure to wear gloves, long sleeves, and safety glasses. It wasn't agonizing, but you don't want that shit in your eyes.
4. Once the plastic is cut out you will see the metal pinch weld. You want to make cuts in this with your sawzall. I made my cuts about every 2 inches, and all the way down to the bend.
5. Once all the cuts are made, begin in the middle, and start hammering the pinch weld towards the engine bay to flatten it down. I tried using a basic house hammer, and even a ball peen hammer. I found it much easier to use a 3lb. drill hammer. Be sure there are no sharp edges left on the pinch weld.
6. During the hammering, you will likely knock paint off the pinch weld, chip off any loose paint chips. Clean the area very well with a degreaser. Sand the area as best as you can. I used a piece of sand paper. After sanding, clean once more. Then spray with undercoating spray. I did about 3 coats total.
Sorry for the crappy "how-to." But that is basically how I did mine.
Stuff I used:
3lb. Drill Hammer
18V Cordless Sawzall w/Metal Cutting Blade
Dremel w/Cutting Disc
Black Undercoating Spray
I also used a floor jack, couple of jack-stands, and an impact driver to make things quicker/easier.