In a TJ, the rear driveshaft angle is a killer. With 21/2 inches of lift there should be no problems, but it doesn't hurt to check. With a CV driveshaft, you want to have the input yoke of the axle pointing at the output yoke of the T-case. With a regular driveshaft, the goal is to split the difference and try to get both yokes at similar angles to the ground. The rear driveshaft is the most important, since you will be driving at higher speeds in 2WD than 4WD.