Brand new to boating; just did my first oil change. After pumping out the old oil, I put back in the amount given to me by the local dealer with the boat level on the trailer. I even put a level on the floor of the boat to be sure. After putting the boat in the water, I did a recheck and it shows about 2 quarts over full. Probably a stupid question, but can you get an accurate reading in the water? Thanks for any input.