I got the van back from Gilette. It took a week, but they replaced the rear main seal, and my rig shouldn't leak anymore. I dealt with Kris, who is a super nice guy. I was really happy with their customer service, their willingness to answer my questions, and their prices. Super great guys.
They talked me out of chipping the van, or even getting extra gauges. They gave it a good look-over and said I have a solid rig that shouldn't need anything for a LONG time. I'm a very happy customer, and I would use them again in a heartbeat.