Well, just got the other one. An eight week old Australian Cattle Dog (aka Red Heeler, Queensland Heeler) her name is WHATCHAmacallit, the two are a handfull. She's too small to ride in the MJ but I'm sure she'll like it also.
It's just a splash guard to minimize water spray/rocks onto the alt, etc. All MJs I've seen do not have it any longer. Of my three only the one I purchased new still has it, and it does get in the way. Safe to remove.
My reverse lights occasionally will not work but if I mess around with the NSS connector at the harness (near firewall on passenger side) they will. I have not tracked down if the problem is the NSS connector or the harness connector since I rarely use reverse in that truck.
And happy 1000th post!
This has some good info and a link to making an adjustable one.
http://comancheclub.com/topic/45839-mj-height-sensing-brake-proportioning-valve-adjustment-procedure/?hl=adjustable&do=findComment&comment=490357
Back in 2004 my wife special ordered her Stratus RT because she wanted a manual. All our cars have been manual except for one of the MJs and her new FJ Cruiser.