I'm doing the same thing, Are you putting in carpeted floors? Phil Rowley helped me out with the design of mine. After fishing in his Jon boat, I noticed with the carpeted floors, there is nothing for your fly line to get caught on. I put a seat in the back and the front using components similar to these...
These won't help you for standing up but you can get extension pedestals to sit nice and high.
Cheers,
Doc