dchinell,
Don't know if you've seen it yet, but there is a relatively new type of line out now called "spiderwire". It is VERY thin for its weight ratings. I've seen it in several Walmarts, Bass Pro Shops and other places. It's a bit pricier than the more common types of line and it will require the use of a Palomar type knot. I've seen it as hight as 200# rating, and it's much thinner than you might expect.

ps
Nice start on your PSK!