Get a Stainless backer plate. West marine sells plates. Find someone with a drill press. Make holes in the plate, slightly larger than the base's holes to give some wiggle room during installation. You will want to install in a garage with some heat if you are wanting to go hit some browns this spring, because the marine caulk you will need to seal the base to the topside needs warmer temps to set. Once you have your holes drilled to match the base...you will need the correct size STAINLESS bolts, washers and locknuts. Apply marine caulk to the underside of the base. If your base has a water trough in the middle, make sure you don't fill that area in caulk....only where the holes are. The trough is designed for water to flow under the base. Place the base with sealant over the mounting location on the topside. Place sealant in the holes, and put bolts thru. Apply sealant to backer plate and bolt into place ( easier with two people). Don't tighten fully. Wait until the sealant is set.....it may take 5-7 days in this weather. Tighten down fully after set.