I crunched the port bow of my P-19 in a very similar fashion a couple years ago. I used a puppy grinder to take out all the crushed glass, then tapered back the edges at roughly a 4:1 ratio. Yes, it looked huge! and felt plenty weird to be assaulting my boat with an industrial grinder. Working one side at a time, I used cardboard inside the hole, pulled to the outside with a couple of snug threads. After laying one layer of glass cloth, I cut the strings and laid a couple more layers to complete the structural repair, then smeared filler over it and sanded, and sanded, and sanded. For coloration, I shot some white Krylon spray paint over it and went sailing. Good luck!