The TJM has separate mounting brackets that bolt to the frame horns, and the bumper then bolts to it. The mounting brackets are pretty stout, about 3/16" thick reinforced to about 3/8" at the bottom. The brackets alone weigh about as much as the rest of the bumper! The TJM also uses some reinforcing L-brackets that rest on top of the frame rails and are bolted only to the brackets, and an extra plate behind the two bolts into the frame horn. On each side, 2 bolts go into the factory weld nuts in the frame horns (thankfully mine were intact), and the third goes through the tie-down/tow loop on the frame.
The overall view:
Another view:
Here you can see the double-thickness of the bracket at the bottom where the portion going back to the factory tie-down point joins the rest of the bracket:
Here the extra L-bracket on top of the frame horn is visible:
4 bolts hold the bumper to the bracket:
A view from below, showing the "air dam" right above the L-bracket:
And last a view from the inside of the bumper towards the driver's side mounting bracket. I meant to mount all 4 bolts with the nuts on the outside
But, you can see how there is room for adjustment in the holes, especially right above the one I have going through from the outside. Also you can see the air dam again.
Brent