The Brits were the ones that really put the Jeep to great use, if you haven't seen these I would like to introduce you to the British SAS Jeeps.
Nothin but combat for these guys! These were used for hit and run tactics in Africa and saw some use in Belgium I believe. Harassing German forces and dragging around small howitzers. Using those tactics a small force of well trained SAS men could harass much larger forces keeping them busy.
Double Vickers for the passenger, one for the driver, loaded down with ammo and gas, and they removed anything that was considered dead weight (like most of the grill)
Oh, and btw.. the Navy Jeeps were used in combat. Often they would be deployed to be used as spotting units for artillery or forward scouts with the landing forces.