I have a 34/35 Snowgoose and had one rudder delaminating so I took it apart. It was actually built in 2 sections and then glassed together. But inside was only plain steel
and badly rusted. I cut it all out and replaced it with some stainless and glassed it back together.
BTW, the mount for the aft steering
box was also plain steel
and nearly gone when I replaced that with SS as well. plain sttel exposed to salt
air was just crazy thinking.