Hello: I just purchased a Scadden pontoon for lake fishing. It is a Cardiac Canyon with 12" pontoons. Thinking about buying a new seat and need some advice: 1. Any advice on a seat with good back & ass support? 2. Is it worth installing a swivel? 3. If so what height would be the best? 4. Does the swivel need to lock in place? 5. Where should I look to purchase all items so they mate up? & 6. Do I need a pressure gauge? Thanks in advance for your replys. Dan Bromley, Grand Junction, Co.