enclose the front of the driveline with a 1/2" brass tube thru the driveline hole in the chassis. It fills and seals the hole which lets in lots of dirt. Extend the tube back to where the clear driveline cover starts and you have a sealed driveline tunnel. In the front have it almost touch the drive hub, just enuf to clear. Use silicon or goop to hold the tube in place to the chassis. In the past I have done full length tubes, but it keeps you from being able to adjust the slipper. This new, shorter tube and stock cover works just right.