Building the beam sockets in to the float hulls last year was an interesting lesson in how much structural stiffness can be achieved by close-fit sleeving of two parts. Since we need the stern tower to be demountable for trucking, the sleeve method sounded like a good thing to try. And the results came out great.
Here are the permanent stubs waxed and ready for the tower legs

Then the tower legs got bolted in place on top of the stubs, and the carbon wrapped around the stub-leg stack.

With that lousy experience many months ago of the beam socket getting stuck on the beam, this time we went with overkill of multiple techniques for non-stick:

Once the carbon and glass combo wrap cured, we released the thru bolts inside the aft cabin, and with a little tap the new sleeves legs popped right off.

With a bit of cleanup trimming around the bases, and pulling out all that wax paper, the finished legs are getting some fairing compound and are ready tomorrow for mounting the cross plates, forming an equipment tower. The sleeved legs are already solid as a rock without the horizontal pieces to tie them together – yea! And the whole tower is coming in at about ten pounds and all hidden internal wire handling. MUCH happier than an expensive, heavy, corrosion prone metal one. Epoxy goo and carbon fabric are fantastic :)