As you can tell I am getting ready to put my boat in the water for the first time. I was checking out the spare stuff like props. I found an extra prop in the engine compartment. It has stamped on it 14.5X17, the one currently on the boat has 15.5X17, is that possible? I thought the first number was the diamater and the second number the pitch. Is it possible I can use ether 14.5 or 15.5?