Hi Brian
We'd suggest getting the block first then going to the hardware store to find the right size fasteners. Make sure to get good stainless, marine grade preferred. Machine screw, washer and nylon stop nut.
Assuming you are attaching the block to the cockpit lip we like to get fasteners that are not too short and not too long. Too short and it is hard to get the nut started on the screw back in its blind spot. Too long and you need a deep socket to hold the nut as it threads over 10 miles of screw. 1/2 inch extra thread is about right.?
Get a pencil and mark the spot for the fastener holes. Don't go too far forward or you drill into the internal hull or forward cockpit bulkhead. Too far aft and there is no clearance for the nut.?
Some folks like to add a thin metal or plastic backer plate underneath the lip. Not needed but helpful. The manufacturer does not add anything other than washers.?
Fire away with questions. Our question is which block are you installing?
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Cheers
Clark and Skipper
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