even easier would be to make a mold of the body without the top, and then make a matched mold of the top section, only 1cm around the edge. in this easy accessible 2 piece mold you can lay produce a half guitar body with a little 1cm inward flange. the top piece, wich is the critical surface for the look, can be a easy flat sheet from a glass plate. first bond it to the lower body, then carefully trim/sand it flush to the body. if you can do a hand laminate in a 1 piece mold, this method will be certainly within your abilities.