Hi I'm Michael
Pick two stationary points close to each other cut your parts and glue and secure.The firewall will be next to your last and the strongest of all of them.If you need parts I can cut them for you as long as I have plans to go by.Ive been kit cutter for years and quite alot of experience with large scale projects.Its almost just as easy to build a new fuselage which I could cut you the parts for that and rebuild a new one ...Michaes