Inspection port replacement fastener question

Hi -

the pop-in inspection ports for my 18 are all cracked so I'm replacing them with the West Marine 6" screw-in replacements. These don't come with mounting hardware but they recommend pan-head screws or thru-hole bolts. I don't have a rivet gun but that's also an option I suppose. Is there a recommendation on what to use? Should I use RTV when mounting the replacements?

Also, being OCD, has anyone found replacement covers for the mounting bolts for the crossbars? I tried to unscrew one and it looks like there's a plastic screw that was glued in??? the cover plate is the little oblong-shaped plate.

Thanks - Mike

Don't use rivets to install the access port. Use #10-24 stainless steel pan head machine screws with nuts and washers. If you use rivets, you run the risk of cracking the fiberglass hull or the plastic access port. Rivets also introduce a leakage path unless you use closed end rivets. Yes, you want to use RTV/silicone caulk when installing the new access ports and be sure to scrape off the old caulk first.

For the crossbar end cap covers, yes, you can probably find them around (I think I have a couple pairs laying around somewhere). The reason people don't use them is because, as you found out, the nylon screw has a tendency to become frozen in the end casting and breaking off. Yes, you could drill out and replace the screw, but most people don't bother. The later boats did not even come with this cover. It is purely cosmetic.

sm