Here's another tip, this one for keeping your boat dry while the work is in process.
I chose to remove all the old ports then prep, cut, drill, chamfer and bore the openings all at the same time but needed a way to keep the boat dry as I was going through the installation process.


I have been using Gorilla Tape from the makers of Gorilla Glue and it is far and away the finest duct tape made. It's thick, does not leave much if any residue, and sticks tenaciously to just about anything.


To seal the port openings, until you can install the ports, start at the bottom of the port opening and work your way up like clapboards on a house overlapping each seam by about 1/2". If you worked your way down water will get in but if you tape from the bottom up the seams over lap so they don't drain into one another.


Even though my boat is covered I didn't want to take any chances, and yes this stuff will keep rain out!