If you are looking to get a skid plate I got an aluminum undercover Fab works one. I have a write up about it on ROF and if your interested could find it. Thinking back I was disappointed that it needed work to fit my 2005 Rubi as the exhaust pipes were changed. Also it was not finished and edges were sharp and needed to be smoothed out. Should fit your 03 with no mod.
I use (and abuse) Rokmen steel skids - one of the first improvements I made to my Rubi. The fit was perfect and you can do an oil change without removing a skid. Mine have been really beat up on rocks and they are still in great shape. I like the weight of steel down low for center of gravity purposes.
As many rock and boulders we've driven over in the past 12 years with our TJ, I do not believe we have once touched the Jeep Medic oil pan skid on it. The trans/t-case skid is very well "touched," but the engine skid looks new.