Hi all, I need advice on a stair to a deck. The stair is 4' long and is a "box" type stair that leads to the deck and is on a concrete base. The problem is the ground isn't level, with a one and half to two and half inch decline. Would shims of PT board of the approriate thickness suffice. I also plan on using carefree fascia over the 2X8 rim josts and header. Thanks.