"Bolstering" swivel seats
 

I haven't done it yet but I think I'm going to. Make up a U-shaped plywood frame just big enough to sit on the deck under the front swivel seats just tall enough you have to lift the seat a bit to fit it under. Then when banging waves at speed you have a lot more keeping the seat under you than an aluminum post screwed in to the deck that is in who knows what condition. Then when you stop and want to spin seats around, throw the frame in the cuddy.