OK- the next step: seat base and creating more storage. I took a cue from this post
about creating more storage under the rear seat by building in a compartment. I enlisted the help of a contractor buddy and creative genius. He had some redwood left from a project, so we ripped it to 5" and built a basic rectangular frame.
With the frame giving us a new height for the seat base, we cut a piece of 5/8" plywood to size and then cut out two large access panels. The plywood was then coated in West System epoxy for strength and waterproofness.
Next step- cushions. I picked up some foam at the local foam shop- I went with a 5x5" high density foam for the front of the cushions and two layers of 2" foam for the main seat. I used a high density foam on top with a medium density underneath. On the left side of the seat is the leftover foam so you can see the different thicknesses and layers.
I went with three cushions, two over the storage access holes and one in the center of the seat that would cover a carpeted step area. I had managed to borrow an industrial sewing machine and had enlisted a friend to help with sewing cushions, but we couldn't get the machine working. The backup plan was we glued the foam to a plywood base (epoxied both sides first) and then wrapped the vinyl over and stapled it. When I say wrapped, we literally wrapped the foam cushions like you'd wrap a present. Turned out well though, I think.
Next step was carpeting the seat box and seat base. That was relatively straight forward. I used marine carpet I sourced through West Marine. I discovered that the original seat back is angled, and under pressure would ride up against the back of the boat. My solution was to cut two pieces of redwood, carpet them and then screw them down to the seat base. You can see those in this picture.
With the modified seat back in place. Looks pretty good, I think.
Center cushion removed to show step area.
This is a view of a cushion bottom. Each cushion has it's own base. I saved the plywood from the two access panels, epoxied both sides, then screwed them to the bottoms of the left and right cushions. Those pieces are sized so they're a tight fit in to the access panels, which holds the cushions in place. The center cushion is pretty well wedged in there, but I'll probably remove all three cushions when trailering.
Completed seat with all cushions in place.
I haven't had the boat out yet (week long trip coming up, we leave Sunday), but based on sitting on the seat and making vroom-vroom noises, I think it'll do the job. Currently in the storage space are two anchors, a 100' anchor line, a 50' anchor line, my tool/spare parts box and my flush hose. Still more room for ski lines and whatnot if needed.