Brand New here 19' foot fishing boat...

Ok.. First of all i have alot of time on my hands... and I acquired a hull and trailer for a 1976 19' Fibercraft V-hull..it appears that someone already began removing the old rotten stringers..(there is an empty fiberglass 'mold' running the length of the boat for each place where the old stringers were) the transom is fine and so thats not a worry. I am going to post each step as I plan to go about it.. and get some ideas and help here.. I have some help and tools but not much experience.. but i' ll take my time and be careful...

First thing to do is make sure all the wood is out I know, but can I leave the fiberglass 'slots' in place and resin in the new stringers or does the old glass need to come out ? I plan to cut all pieces from foam and use them as templates.. to make sure they all fit well... I know this is gonna be alotta work and a long process but it's ok ... I have time and I'm not lazy...=)