I cut roughly 3 inches in the front, and then rolled the lip in. It goes up to the body line. The rear I cut it out as far is it would go into the inner wheel well, and rolled the lip in also. Be careful with the rear because there are 3 layers of sheet metal there, and when you cut it they come apart and are a pain in the ass to roll all 3 of them together. As far as cutting them I used my air cut off wheel, and sawzall. I rolled them in with a pipe wrench, and finished off the lip with a hammer.
It has rough country upper control arms, Jeep grand cherokee coils in the rear, cranked torsion bars, rough country shocks, and stock 4.6 gears. The only time I notice any power loss is in 5th gear. The 2.4 doesn't have much power to begin with. the 4.6's help.