For now I will spare the hole saw:-) What I've decided to do is make a panel out of plastic or wire mesh porch door screen material, that will be trapped
My boat is also from early 70's. I installed a 6" inspection port in the aft surface of the well - mainly for drying out the boat since it was given to me
So there's stuff you can keep in your pockets or attached to your life vest, but other stuff that needs to find a home somewhere in the boat... without it