First board.....Using a surfboard blank

[tenover]

I've built a lot of surfboards the traditional way, and I have an old blank I'm going to shape into a kiteboard. This will be my first board, and I live in San Diego, so it has to handle light wind conditions, but given some "issues" with the blank, the dimensions I can get it down to so it's bidirectional is 137x44......Will this be ok? I'm 5'8" 160lbs.. The core will by Polyurethane foam with a balsa stringer down the middle lengthwise. Any suggestions on how thick I should make it? I'll have to handshape it just like a surfboard, so I can bring it down as much as I'd like, and can put in dome on the deck and concave if need be as well. I'm also wondering if I should go the vacuum bag route or just glass it like I would a surfboard, maybe adding a layer of carbon on both sides as well.....? Any advice is much appreciated. Thanks.