I bought a Big John Planer Board mast years ago for another boat. The mast has a plate on the bottom with 4 bolt holes to bolt to another plate which is bolted permanently to the boat. I am looking for a adapter that fits in my chair hole in the bow of my Lund Pro Sport. Any thoughts on where I can but one of these? I am sure I have seen a mount before that just slides into the hole where my forward seat would mount. Thanks