Use BedIT or 4200. Most of us will recommend BedIT because it is so much easier to work with and remove in the future. Remove the cleat, countersink the holes from the outside, clean up the hole (I dab BedIT on the hole to collect the dust), wrap the underside of the screw head and about 1/4" of of the exposed threads closest to the cleat (sealing screw threads to bottom of cleat), reinstall and remove excess BedIT with a razor blade.
Make sure you use proper backing plates. Fender washers are typically very thin. I actually prefer non-stainless washers because rust is a sign that the hardware needs to be resealed. There will be many opinions on that. Don't forget to use nylon lock nuts. I've used BedIT in a pinch to keep nuts from coming loose. Takes some work to remove in the future though
Originally published December 2003 *Moved & Edited September 2017 Bedding With Bed-It Tape 5/20/2022 IMPORTANT UPDATE BED-IT TAPE IS BACK PURCHASE BED-IT TAPE Countersunk/Beveled Hole Over the years,
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