Hi Carimt. I built one of these models many years ago, they are a superb way of understanding the intricacies of ship building, like yourself the model I built cried out to be put in the water. The model I built was constructed entirely of card as per kit, when complete; the outside was covered with several layers of resin and left to dry completely, after that she was treated exactly as you would with a fiberglass hull, like yours she sailed well and looked every part a real ship.
The only problem at the time was transportation, I had to rely on a friend who had an estate car, eventually he sold this and she had to be disposed of, I was amazed at the strength of the model having to take a Stanley knife to dissect it for disposal, just retaining the mechanics and prop for future use,?.
I am at present building a ferry at 7 foot 2 inch, but now have the means to transport it.