I made that mistake at one point when I was doing a MML. If you leave those nuts tight, you'll find that the whole Jeep goes up when you lift the transmission instead of just the drivetrain.This was my plan. I’m still having trouble seeing why the transmission mount bolt need to be lossenedmin order to support or jack up the engine a couple sixteenths of an inch so I must be missing something here.
It's four nuts at 25 ft lbs, IIRC. Worth the time and trouble to loosen them.