Due to the stepped hull you are a bit limited with the width and the 12 x 12s seem to be the best option.
Even though they work for Skiblet I would not advise using the ST16s with only one actuator. In September a fellow lost an ST16 by not using the correct mounting plates and only one actuator
http://www.offshoreonly.com/forums/g...tic-ocean.html
Tom
Bennett Marine