I don't think fiberglass will differ any from a graphite rod. If you are going to buy all of the components, it will be a very easy build. Now you can make it more complicated and buy cork rings and shape the grip yourself. If you have a lathe, you can turn your own wood insert. Other than that, it is only a matter of wrapping the guides and gluing the handle and reel seat on. There are a lot of books and info on the web about rod building. If you go to
www.rodbuildingforum.com, you will get all of your questions answered by some very knowledgeable builders.