Bent cage and crossbeam

[DrG]

We had a great time at the Hill Country Hummer Club event but I've had a annoying rattle from under the truck ever since. This is a minor version of the rattle the H1 factory service guy fixed by pulling the cage off the exhaust pipes with a floor jack after Saturdays run over the rocks. I took my H2 in to the dealer today and they are telling me I need to replace the underside cage and a crossbeam to the tune of about $525. The rattle isn't THAT annoying and I certainly fail to see why I would replace the cage just so I can bend it up again but the crossbeam has me concerned. I can see that one of the three rear attachment points at the rear of the cage is not flat against the crossbeam like the other two and I assume it is that crossbeam they are talking about. Can this bent crossbeam cause me any other kind of performance or alinement problems? Can't I replace the crossbeam myself? They still have my H2 tonight so I can't see that part but isn't it just a bolt on replacement. I'm just wondering what the worse case senerio is if I don't fix it.
David