Create a box by nailing select pine planks together with 2-1/4-inch nails.
Nail the shelves into the box, spacing the bottom three shelves far enough apart to place baskets with a 1x8 under them.
Cut a shallow piece of plywood material to fit the back of the shelving unit. Use construction adhesive to attach to back of shelving unit and secure in place.
The lowest drawer runners available are 12 inches long. If your shelving unit is shorter than that depth, use a reciprocating saw to cut out the center section of each runner, keeping the back and front of them.
Using a hacksaw, cut a 1x8 board to the width of your shelf to create a shelf base for each basket.
Screw the drawer guides to the base of the shelf. The front half of the drawer runner will sit flush with the front of the drawer base, and the back half of the runner will rest against it, extending over the back an inch.
Attach the base of the shelf to the bottom of the basket with construction adhesive and two or three 1/2-inch screws. The back of the basket should protrude from the back of the shelf base by about 1/2 inch. The front of the basket will extend past the base of the shelf and shelving unit by a few inches.
Screw the other half of the drawer guides to the inside of the shelving unit. These should sit directly on the bottom three shelves, and the front half should be flush with the front of the shelving unit, with the back half resting against it.
Slide the drawers onto the tracks.
Shim and nail your shelving unit into a wall cavity, cut to unit size and paint as needed. Use the unit to store spices, plastic wrap, and other shallow kitchen items.