So the plywood under the shell just came out. Are the elevator bolts out. Typically it is necessary to take the lower interior panel off to repair the floor on the edge like you have. This is to bolt it to the frame. There are numberous discussions of these issue and you can find several opinions and creative options in the floor repair sub forum. Looks like you will need the gluing a splint technique. I think you will have to take off the lower panels also.
