This is how
hydroponics baskets should fit snugly. The holes should be facing the same side as the openings of the gutter elbows.
Use the hole saw to cut a 22mm hole on the underside of one of the gutter elbows 3 and position the grommet in the hole. Fit the irrigation pipe through the grommet. 3 Cut two 22mm holes in the lid of the crate. 4