Yup. At the VERY least, you need to be able to rotate your rear axle for proper pinion angle meaning you need adjustable upper arms at a minimum, and IMHO, an SYE is an absolute must for any lifted TJ. (Because you can't rotate the drivetrain down to get matching angles on the U-joints, an SYE is helpful.)
97 TJ Sport - 4.0/HP D30 w ARB/8.8 w LS/4.88s; 35s and flat fenders on 2.5 lift
84 CJ7; frame off restoration in progress.
The technical advice you get from me here is worth exactly what you paid me for it. Warranty issues will be reimbursed at double what you paid me for the advice.