I glued it with cyanoacrylate glue, but only after about a month of cutting and gluing shims into the vinyl's interior. This created an interior skeletal structure that kept the warped vinyl as straight as possible. A complete pain in the butt, and a severely daunting task, but necessary.
After it was glued, I spackled the seams with Milliput and lightly sanded. You can't really sand vinyl.... like I said - everything about this model is a challenge, but worth it!
Fantastic Job - Got this one sitting on the workbench so I know what a monster it'll be to get the results you did! To answer LAs question if I remember the kit should build out to about 18" long when it's done.