remove the sensor and patch the hole in the fuse its a fuel magnet and the wood will soak it up, mine did and I regret not sealing it up sooner,I found the soft wood when I stripped the fuse.
mine is now a float plane and I needed the area for a float mount it took a little surgery to replace the soft wood that could have been avoided by some iron on covering or a sticker.
I wouldn't glue the tail in when I stripped the airframe of covering I found several cracks in the tail area that wouldn't have been found if it were not for the fact I could remove the tail surfaces.
Adui its time to punt that instructor and move on to a more flexable and kid friendly instructor for sure.