Though this kit is a very simple strut spacer lift, Rough Country offers the option of adding new upper control arms with heavy-duty ball joints. If you opt for the arms, you'll have to start this kit with a 0.500-inch drill bit. After disassembly of the front end, you will have to drill the very bottom of the tapered hole on the top of the knuckle. You will not be changing the taper of the hole at all, and only be "skinning" the very bottom of the hole to allow the new ball joint to go in. Even after the knuckle is slightly drilled, you could still go back to a stock ball joint without any problems (we checked).