http://www.surlybikes.com/spew9.html
I am going to buy a LHT frame as soon as the 62cm are in stock. Right now, I am planning to rustproof the inside of the frame with Boeshield. If I have any trouble finding that, I will probably use Amsoil HDMP. Boeshield, Amsoil, or Framesaver should all be more than good enough for your needs. Be sure to use it in a well venitlated area and give it time to "dry" before you start installing the components.