A note on Kindwalls "Swiss Cheese":
I rebuilded my diff last night. It took me about 25-35 minutes in total. I think I could do it 5-10 minutes faster if I try to do it fast. So the tradeoff with a open drivetrain to get more weight UNDER cg seems like a good one if youre ready to rebuild your diffs between qualifying and finals(or more often). The thing is, since he is a team driver he gets new diffrings, carbideballs and such when ever he wants. I'll stick to my closed drivetrain and rebuild my diffs more seldom.
/TeeJay