To fit the hinges, the space must be correct between the bookcases. Quarter-inch spacers are usually included with the kit (image 1) and clamps between the two units (image 2). Make sure the tops are level when locked into position.
Positioning the hinge is important to keep the shelves straight. Start at the top and put some screws in there, bottom and center.
Use a hole centering bit to pre-drill a hole in the first screw hole at the top of the hinge. Pre-drill the holes for the screws. Do not fully tighten the screws until both are on.
Fully tighten the screws into the hinge making sure it is perfectly straight.
To attach the bookcase door mounting brackets, the pivot points of the sill and valence must line up. The edge of the door should be flush with the trim (image 1). With the valance and sill in place, make sure they are evenly spaced at both ends (image 2).
Mark the threshold with tape. Then remove the valance and move it over 5/8 inch to allow for trimming, and comment on it.
Drill pilot holes in the sill (image 1). It will be secured directly to the subfloor and then the sill will be secured with 3" deck screws (image 2).
