Place the polyurethane boot in the housing. Whalen dabs some axle grease on the inner splines of the axleshaft to help the shaft slide through the factory inner seal without damaging it. Gently work the new axleshaft in place. RCV Performance includes a tool to help you get the boot to seat on the CV joint bell, and Whalen has found that a bit of grease on the boot makes it even easier. Justin also likes to use antiseize on most of the bolts and anywhere that metal rests on metal to make future disassembly much easier.