Step 7: Install inner barrel.
Cut off about 6 inches off the top (open end) of the inner 30-gallon barrel. The barrel will go into the hole upside down with the open end down. Cut a small notch on the edge of the barrel so that the STS-2 cable can freely pass underneath it. Carefully place the barrel over the rose cones and sensor without disturbing them. Make sure it does not touch the rose cones when it is in place.