Keep them with the airplane documentation
Keep them with the airplane documentation. They are helpful for maintenance and modifications for your own use but more importantly they will be EXTREMELY valuable to anyone who eventually buys your airplane (well they should be anyway). I rolled my loose drawings including the ones I made for the electrical system and the autopilot installation and put them on a shelf in a closet. The ones that came in the preview plans book are in the book on a bookshelf in my den.
Bob Axsom