[Caymanboy]

The old floor has glass on top, with gelcoat on top of that, the bottom may have a layer of glass or just coated with resin, it is usually just mudded or bonded to the stringers and pressure points with Potter Puddy, most times in older boats it has come loose in some or most spots. Really not too hard to cut out, measure twice and cut once they always say, the hatch will want to warp after you cut it.