Hey guys just bought some of what I think is the go-to outdoor carpet adhesive for most john boat converters but I am confused. Everyone seems to say three coats of spar varnish on marine grade plywood then carpet with adhesive. But, the can of adhesive says do not use on stained, painted, or water sealed surfaces. It also says not to use on urethane backed carpet which I'm not sure if what I have is polyurethane backed but it appears to be rubber backed. So staples?