For many years I have put felt soles on boots and waders that were only available with rubber cleated soles. The procedure is time-consuming but relatively simple. Grind off the rubber cleats to create a smooth surface then apply the felt with contact cement. So when I got my new breathable, camo, zipper-front waders with cleated soles I started grinding. Much to my surprise, the cleats weren't molded of solid rubber like usual. Instead they were molded from rigid but porous foam with an 1/8" skin of rubber over the surface! In grinding, I had destroyed the thin rubber coating and rendered my brand new and expensive waders useless. Thankfully the seller understood the problem and gave me a brand new pair of waders. (I don't think the company even realized there had been a design change.)
So, how to proceed? Instead of grinding to make a flat surface, glue strips of felt or rubber sheet between the cleats to achieve the flat surface. Now glue on the felt as usual and install hex-head sheet metal screws.
Hope this helps some of you avoid the unpleasant surprise that I had.
May the River Gods smile upon you.