Sooo many ways to lighten a vehicle. It boils down to personal preference and budget which ones are going to work for you. These are general ideas for any vehicle, not just jeeps.
- Remove carpet, floor mats, etc.
- Remove stereo, speakers, amps, etc.
- Remove paneling, padding, or insulation that isn't needed.
- Purchase lightweight racing seats for front.
- Light weight battery
- Remove air conditioning (that alone will save over one hundred pounds)
- Replace exhaust manifolds with headers.
- Replace exhaust system with a lighter aftermarket one. (no cats, etc)
- Purchase lightweight replacement panels such as hood or tailgate.
- Lightweight bumpers, or just remove bumpers.
- Remove doors, or other panels that are not needed.
More extreme ideas:
- Go through engine bay, interior, and under carriage and replace brackets with zip ties.
- strip down all wiring harnesses of excess tape and loom.
- Go through engine bay, etc and remove any heat shields, insulation, etc.
- Replace transmission with a lighter, custom racing trans
- Purchase custom aluminum driveshafts. (May not be a good idea in a jeep)
Literally any vehicle can lose between 500-1000 punds by stripping items off. You have to be willing to make sacrifices though! Every ounce counts! If you save a pound in a hundred places it's a hundred pounds!
There are other ideas I forgot to list, but I'm tired right now, and having a few beers.