I took off the wooden handrails on my boat. They'd been sanded so many times they were paper thin and leaking. The boat had identical railings below deck and top and bottom were bolted together through the deck. Didn't want to mess with any more wood topside so decided to go with Stainless rails. Found a supplier that had 2' long rails that through bolted from beneath. Carefully drilled the bolt holes from above. The deck was just the right thickness for a stock length 1/4" machine screw so didn't have to mess with cutting/grinding down the fasteners. Screwed the old interior rails from above with countersunk #12 self tappers and glassed over the screw heads. Faired them in in conjunction with painting the decks. Figured that screws buried in about 1 1/2" of mahogany were going to be plenty strong and they have been. No more leaking handrails and 4 less pieces of wood to maintain on deck. Replaced the 5' long wood handrail with two 2' long SS rails spaced about 8" between on the main cabin top and one 2' long SS rail to replace the 3' long wood rail forward.