The leather was one whole piece. It does not require glue to install, only staples on the backside edges where the leather wraps around. I used 1/4 “ staples and they came though the other side of the backer board. The original staples are a hair less than 1/4” and the replacement staples are 1/4” but the new padding covers the protruding staples tips and are not an issue with the leather. The thread on replacing door backer board is below.
https://forums.pelicanparts.com/porsche-911-technical-forum/1025491-replacing-door-panel-backer-board-cheap.html?highlight=Door