Re: 1983 thundercraft needs new floor....
Removing the floor is the easy part. A circular saw works great, set at whatever depth your floor is, and care taken when getting to the edges so you don't go through the bottom of the boat. An angle grinder works well to smooth things up when the floor is out. In my experience, these floors rot bottom up, not top down, which means you likely have saturated foam and rotted supports & stringers....
- Scott