No, I didn't and you don't have to, but can, because the Bilstein 5160's (25-242515) specifications are 0-2" additional travel. With the Bilstein 6112's on the 3rd ring setting and the 5160's on the rear, I still have almost 2" rear ride height difference from the front and a huge, night and day improvement in ride quality. The 6112's have more damping and are much heavier duty up front than the 5100's, but the 5100's, front and rear are great shocks and the Bilsteins are far superior overall to anything else.
Note: You need a serious commercial spring compressor to assemble the 6112's or have a shop do them.