I agree that the dirt track input is really not applicable, but I can't refute that it probably defines an extreme - maybe not one that has any bearing, but an extreme. My chassis is complete with the driveline and suspension details fixed - triangulated 4 link with coil-overs. I have the option of adding a spacer to the transmission mount to flatten it out a bit from the six degree drop that it has now. I have already done some minor clearance surgery on the glass tunnel, and doing a three or four degree lift (to get to the 2-3 degree range) would mean some more involved major surgery - not a big deal with glass, but is it necessary?? That would, of course, increase the driveline operating angle, which is not necessarily good. I have yet to find any written direction that defines some ideal driveline angle, only very clear and specific guidelines that the transmission and differential angles need to be equal and opposite, and further that the operating angle (angle of the driveshaft due to the differences in elevation of the transmission yoke and the differential yoke) is ideally three degrees or less, but not zero, and that if it is more than three degrees it must be less than the limits of your U-joints. Look at some of the Jeep and lifted 4x4's to define extreme. If I am wrong here I welcome guidance with specific references to back up what is wrong.

I think that I will unhook the transmission mount nuts and jack up the tranny to see how much I can decrease the angle without more tunnel surgery. For the tranny I'm OK with a pretty small clearance since it's triangulated and does not lift much with any engine roll. Then I'll go ahead and pull the body, and make necessary mods to the tranny mount while it is accessible. If some additional clearance work is warranted, so be it.