I've found that The Right Stuff works excellent for sealing oil pans, front covers and so on, on my old CTD's, so I would imagine it would work just as well on the IDI too.
Also, when I ran my OTR Freightliner with a Cat, we used Rotella at the terminals, and whatever we could get on the road. I had an on the road service, and got Delvac 1300 for oil. Previously, on a motor with under 200k miles, I averaged 3 gallons use per 15,000 mile oil change. With the Delvac, it only used a touch over a gallon before the next service. From then on out, I requested Delvac, and would religously add 1 gallon at around 10k miles, and the level would be about halfway down the SAFE area when it came time for a service. Several other drivers also noted similar useage.