What years were Hulls made of Solid Glass

[Figuringitallout]

Just sold my cruiser and looking to buy a sail boat next.
With that said I learned alot on this last boat in regards to what I want and dont want in a boat (construction wise).

My questions is what year did the Catalina 30' have a solid glass hull with no Balsa wood, Plywood or anything like that in the hull bellow the water line?

 

[mikeracca]

When looking into my hull I can’t see any signs of a wood laminated in my hull structure… that of course doesn’t mean much as I have never dug into the hull at any point to know for sure. My C30 is a 1979.