Some of my thoughts:
The only way to go all the way through would require putting sleeves in.
No it doesn't. Sleeving the uni-body would allow the bolts to be tightened tighter, but that's not necessary at all in this application.
Of course, a customer could sleeve their own uni-body easily enough, whether it's ours or yours.
On the driveside it would require moving the brakeline hardlines.
Yep. But they don't have to be relocated- just popped out of their mounting clips long enough to drill the holes. Then, just remount them when done with minimal if any bending to fit. Easy enough.
Another point to be made here. I'm assuming the JCR skid is normal mild steel?
We use higher grade 50,000psi steel in all of our Rock Attack Products, so we can achieve the strength of a much thicker skid with less weight.
We avoided using 1/4" steel for that reason. Personally, I like to keep the weight down on my XJ's anywhere I can if it doesn't sacrifice strength.
I also prefer through bolts and nuts over self-tappers or even nutserts when mounting in a uni-body for the strongest mounting points.
No question our bolts mounting through the crossmember will provide a much stronger mounting area than the self-tappers on the front of the JCR skid.
Clamping the skid to the crossmember is what helps "unitize" that entire structure together and creates a more solid rigid foundation- as opposed to the skid kind of floating on the bottom of the crossmember.
YMMV.
(I'd be afraid of catching the rear edge of that skid on a ledge I'd just dropped over if I had to back up again.)
As for cat protection and clearance- If you could extend the ENTIRE full belly skid rearward until it covered the cat, you would see why a skid like that would be ridiculous. It would have to be divided (weakened) to clear the driveshaft and it would eat up a LOT of ground clearance under the belly for no reason. It would also be a behemoth and weigh a ton. I don't worry much about the cat as it's located farther rearward towards the wheel, which offers it more natural protection than being in the center of the jeep. I haven't destroyed mine, and we wheel in big rocks.
A skid that covered the cat only would also suffer from extreme heat transfer from the cat.
That can cause the skid and the uni-body above the cat to rust much more quickly if it holds heat in that small area.
I also don't clearance our skids for cat clearance. Any relief cuts or dips away from a straight rear edge create points that are easier to bend. That's why I don't like the t-case skids that mount on one side, covering the t-case in a triangulated mounting situation. The rear edge is easier to bend and it doesn't protect the entire crossmember.
I prefer a straight across rear edge for max strength and rigidity.
Guys who run the big round cats can replace them like Wink did, but I know for a fact that a good exhaust shop can make those fit with minimal cost.
The earlier cats usually don't require any exhaust mods at all.
Covering the front of the cat alone actually offers a great functional level of protection, as it allows the obstacle to slide past the front mounting point of the cat and over the body of it.
As for copying- no worries here.
I have a bumper in mind that looks almost identical to the JCR unit- kind of freaky how close it is to their design, but hey- there's only so many ways you can build a bumper, right?
I think it should sell for about $10.00 less than theirs...
