Word to what Sean said!!!
Go to a surf shop, and see if they have any scrap fiber laying around. Thats what I did when I repaired my surfboard!!!
You def only need a little layer. Its not so much "building" the material up
Its just getting that seal down. You might put a little more on the edges, where the wood butts up (love that game!), but you should be good with about an 1/8 of what you put on! LOL