P.V.A is used by all fibreglass manufacturers world wide. We commonly refer to it as "release agent" (as opposed to release wax which is what we put onto moulds before the release agent is applied) You can spray it on, sponge it on, brush it on, or even put it on with a rag, but for best effect it is applied as thinly as possible. To put it on a hull for transportation would work fine except that if there was the slightest amount of moisture in the air ie rain or even wet roads, it reacts to the application of moisture so well that it would dissapear off the hull in the first few minutes of travel when wet.
Darryl J Barrett