Use Jeep-recommended Mopar RTV or a high-quality equivalent. I run a uniform, 1/8-inch-wide bead of sealant around the rear case half. Circle the bolt holes, and stay in the center of the machined surface. Since the halves are precisely machined, the mating faces will squeeze sealant over the surface. Excess sealant is unnecessary. However, you must make sure there are no sealant gaps that could leak.