I am building some built-in units that will have doors that have a beadboard panel in them. The style of the doors is Shaker. 3/4 poplar will be used for the rails and stiles since it will be painted. For the beadboard panel should I use 1/2" or would 1/4" be fine? I realize that if I use 1/2" I will have to route a rabbet so that it will fit into the 1/4" dado on the rails and stiles. The overall door sizes are 15.5 x34 and 15.5 x 20. I am planning on 1.5" for the rails and stiles.