I've had two Stickit IV planes. I built the first one that you see in the avatar, the second one I bought used.

The first one had the servo arms hidden inside, the second one had the servo arms exposed. I highly recommend going with the exposed servo arms because it makes the linkage setup a lot easier.

Both planes used a 1/16" music wire pushrod on the elevator with two small equally spaced nylon guide tubes to keep the pushrod from bowing.

Both planes also used a pull-pull cable for the rudder. The first used two small guide tubes for the cable, the second used only a single guide for the cable. The single guide worked just fine.

I ran a 4 ounce tank on my Stickit, which is the size I'd recommend for sport flying.