Okay, the next couple of steps require bending wood pieces pretty significantly. That involves soaking the piece in water, gently bending by hand, then either heating the piece with something to lock it in position, or locking it in place and letting it dry. I went the second route. Here's the two pieces... I decided to use the piece the deck was cut out of to shape the new pieces, since they'd be lining up with that curve. It seemed to work well.