To sink it in you'll want to use allen head and counterbore each whole (countersink or counterbore i cant remember) Im sure you could bend it yourself, as long as it wasnt too thick, but yes i'm sure it would be a bitch to do, but could save you a couple hundred bucks possibly. I wouldnt want to notch it like that guy did. I can weld aluminum but i'd rather not do it to much. Find out how much you'll need, i'm pretty sure i could do it in the shop relatively easy though.
It seems recently i've seen a lot of Jeeps wishing they had more weight in the rear to keep it balanced with the front, WideJ comes to mind as well as a few others. Sticking with steel could be more beneficial for that matter but less bling. I like the thought of aluminum armor but im not sold.
And why on earth are you putting leaves in the rear of a TJ?
If you say its because of cost then i call B.S. and call your bluff. Putting leaves on the rear of a TJ is like swapping out the 4.0 for a 2.5, your not necessarily starting with the best, but its a whole lot better then other option.