You have some "fun" reading ahead. I'm fairly sure the neoprene idea has been discussed on CF and the butyl tape procedure is on Maine
Sail's site. Other goos have all been tried and discussed. One guy a couple of years ago was going to use aircraft windshield sealant. My boat doesn't go anywhere fast enough to need that.
Neoprene under the stanchions
? I don't think that's a long term solution. Go immediately to Maine's discussion of butyl tape compared to Don Casey's Goo Method. Sorry Don, I know you are the Pro From Dover, but I'm going with the butyl this time after more than one failure with tube goo. Opening ports
just arrived. Maybe this doesn't matter any longer now that all boats except mine have A/C.