Hey Dave! Many variables here.... how the boat "settles" onto the trailer, the type of trailer, what do you have on the top of the boat (radar arches/canvas arches and such)..... but, when getting the door, you may be able to get a tax credit if the door is insulated. Higher and wider is always better, and the less you have to do each time you want to move your boat in and/or out of the storage garage area, the better....and less to forget and start an unintended home improvement project.
Byrdman