The first thing she tackled was the bench. She assembled the BESTÅ TV unit and rested it on the baseboards and some pieces of wood painted to match the floor.
Then on top of the bench, she added the 2 small BILLY bookcases on left and right. They just sit on top of the BESTÅ and were mounted to the walls around it. The extension units were secured above the BILLY bookcases.
To make the units look built-in Jessica used a 1 x 4 where the BESTÅ meets the wall.
After that, she installed the shiplap panels cut out of scrap plywood. The first board was able to sit on the 1 x 4. The top piece of shiplap got a shelf added to it before it went onto the wall.