assuming your lift was installed properly then you should already have the rear track bar bracket...which if you dont have the bracket that could be part of the issue cause your rear axle won't be centered. id spend the money for the sye cause it gives you the best option/upgrade.
05 Tj d44's, 4.88's, ARB's, 37's and some bling
99 TJuggy tons, 40's
14 RAM 1500
07 SRT 8 grand