Ok here is how to glitch the BB. I can beat the BB with only myseld and one other crew member. First kill the officers. Second grab the wheel. Behind the ship is a dock and a rock to the right of the dock. Simply turn the ship around and kind of park the ship up against the beach between the dock and the ship(front towards dock. u should see the back end of the ship slowly start entering the mountain. once thi shappens keep pressing forward and use full speed or ram speed and u shoul ddrift across the beach into the mountain. Now just sail straight till u are back in the ocean. Now just sail around the island(to the left) you should come up on Goliath with full hull. Now just blow him awaya.
It is sometimes hard to get in the glitch but I have pefected it. I can usually do it on my first try now. Let me know how it works for you guys.