Required BL will come with kit. Don't be afraid of a BL because you can only make your Jeep more capable with one. Our skid will be cost effective. However, to install it will not be. You will need at least adj upper control arms to set the pinion angles, exhaust mod and SYE/CV DS. On the 03+ you will gain at least 4" belly height. That's like putting 8" larger tires!
I am all for a BL, in fact, I am planning on doing one one day, I just don't know when. When I got rear ended, my shop was going to have to take the body off to weld the new rear crossmeber in, but they were thankfully able to straighten and strengthen the existing one. Taking the body off would have meant money out of our pocket because there was no way our body shop would put it back on with the current body mounts. They are dry rotted, just not the the point of causing damage issues. I have decided that a BL that replaces them would be the way to go, especially since they allow for full clearance TT, and higher gas skids.
As for needing a sye/ds and UCAs. I was also planning on those, but I was hoping to be able to avoid them for now. This vibe was my first issue. Since I won't be able to get away with 4" of clearance and no vibes, I will just have to suck it up and burn through the money needed to do it right. That just means it will have to wait some. There is no point in getting rid of a vibe that doesn't cause issue, just to get another vibe that will actually cause problems.
I couldn't care less about exhaust mods. The stock system is fine, but it sounds like it wants to die above 3k rpm. I believe the Flowmaster 40 series is much shorter than the stock one, and it should fit the bill for any required mods. I may be wrong there though. It only took 2 hours, and $100 to do my dad's Dakota with all of the parts and muffler. The biggest PITA was that his truck is lowered, and it was very cramped trying to work under a truck that has ~32" of clearance when jacked up.
Time to start hiding some more money to do the sye/ds. I think it is really cool that the kit will come with the necessary bl. Have you guys determined a size for it? I would imagine it will fall around 1"-1.25". Will it replace the factory bushings? If so, I would be all over that.
I really appreciate all of the answers. I almost started building my Jeep a few months ago (well, actually more than 1 year ago), but the mother issue got in the way, even with my own money. I guess it is a good thing in the long run since I have learned so much more. I would have already messed the Jeep up with a less than ideal BB with stock shocks.
Keep up the great work guys. I can't wait to see the pics of this thing.