Platt used an air cylinder hooked directly to the lever on the tail wheel, it works but there is no down lock, if the air pressure gets low the tail wheel would start to retract with any pressure on it. I'm using fishing leader for steering set up in the standard way using a PC board pivot arm of course.

You put a lot of detail into your plane, I did not see your exact glassing method, but with a light weight method you can save much weight! I could definitely build a lighter fuselage, but I want to use this one so we shall see what the weight is. My tail wheel is just under 1oz in weight, not sure what the plastic robart one is or some of the other methods used in this thread, but it is as light as I can possibly make it.