Derek,

Your Guillemot Double will be easier to install a rudder in than most singles. I am making a rudder and foot rest for my double and just completed the inside fiberglass strips today. I plan to add the rudder and foot rests later.

Will your rudder and foot rests have external screws showing?

I may complete the outside glass strips and end pours then add the rudder.

Will keep you informed of what I learn! Go for it! Steve in San Diego