How to make a cello out of duct tape?

My friend and I are planning on making a cello out of duct tape. We have a cheap cello that broke (out teacher gave it to us because the back fell off of it). We were planning on forming the duct tape to the cello layer by layer, until it was stiff. Then we would connect the back and the sides (with duct tape, of course). We'd then put our label on the inside, and put two sound posts for strength. Each sound post would be made out of wood or metal. We don't know yet. After we connect the sound posts to the back of the cello, then we would put the top on. The top would be connected then. For the endpin we were going to increase the amount of duct tape layers, and then use an actual endpin and pin (I'm not exactly sure what the piece that holds the endpin is called). For the neck, we would create a mold (probably out of duct tape). We would put some layers of duct tape on, then possible a wooden or metal rod for strength? Then cover that with more duct tape. For the fingerboard we're going to take the fingerboard off the broken cello and duct tape it to the new cello. For the bridge and tailpiece we would use an actual bridge and tailpiece. We are trying to figure out what to do for the scroll and pegbox. One idea is to attach an actual pegbox and scroll to the wooden or metal rod that would be inside the neck? Other than that we have no ideas. Please give us any ideas that you have. Yes we know that the cello will sound terrible, but we still want to do it. Thanks!