I'm a big fan of always having a multi-tool with me, be it a Leatherman or otherwise. If you have one lying around, here is a 2 minute, DIY mod that'll cost you about 5 cents, not take up any (usable) room in the Jeep, and keep the Leatherman with you on every adventure.
Materials & Supplies
Step 1: feed zip ties through slots in tailgate
Step 2: feed zip ties through carrying case
Step 3: tighten them down
Step 4: snip off the excess
Step 5: put leatherman back in