So, I went out to the garage last night to pull the cover off and hook the battery up. Looking under the car for Spring time leaks I found my newly rebuilt D60 was leaking on the passenger side. I had this entirely rebuilt by a local shop and installed it in the car assembled. There was some oil built up in the pad, so it must have started leaking right before I parked it last winter. Axle is a Ford unit that was full float I had regular Ford semi float ends welded on. Has an Explorer rear disc kit..

Never had one of these apart. Do you guys think this warrants cracking the cover, or can I get away with just replacing the gasket and seal on the outside? Thanks...