Step 7 · Connect the Plumbing
First, connect the drain discharge tube. Place the rubber gasket inside the disposal's discharge outlet, then attach the L-shaped discharge tube with the metal flange and two screws. Next, connect the dishwasher drain hose to the dishwasher inlet you prepared earlier. Slide a hose clamp over the hose, push the hose onto the inlet, and tighten the clamp securely with a screwdriver. Finally, assemble the new P-trap. You may need to dry-fit the pieces and cut the pipes to the correct length with a hacksaw or tubing cutter to align properly between the disposal discharge tube and the drain pipe in the wall. Once sized, connect all pieces and hand-tighten the slip nuts, followed by a quarter-turn with channel-lock pliers.