I did a similar thing last summer with my new Blade. I hit a submerged rock with my daggerboard. It barely slowed me down even though I was on a broad reach in only 10 knots of breeze.It twisted in the trunk and caused the hull to fill with water. A good friend helped me repair the dammage. We ground off the deck plate to make it easier to get inside for the repair. There are a lot of guys on this forum with a lot more experience with fiberglass than me. My only suggestion is that you make sure you glass in the new daggerboard trunk correctly. A small error may make a big difference in the orientation of a high aspect daggerboard.