That wood "keystone" seems attractive, but also a lot of work and a hassle to store in a rolling boat.
Perhaps an adaptation of the stock Olson slide out fill piece? I realize that ours works well because the mold for the forepeak section has a shallow recess for the slider to move forward and back. I got to thinking tho... that recess is only about 5/8" deep. Factory finish was piece of Formica-top plywood with a teak trim on the aft edge. That piece of trim had been ripped out before we bought the boat leaving ugly screw holes. The trim is needed to help keep the fill piece in place, i.e. keep it from sliding aft and falling off while the occupants toss and turn in their sleeping habits... or toss and turn for other reasons...
I replaced it with a same-dimension piece of honeycomb skinned with a couple of layers of glass, with an extra piece of 2" glass tape underneath in the rear where support is needed. Then I milled (fancy term for a klutzy amateur) a piece of teak trim that is glassed to the rear, and invisibly glass taped/tabbed to the surface on the inside. The panel is painted with EasyPoxy and the teak trim is varnished. This supports my 210# sitting weight with no problem.
When the fill cushion is set aside, the panel slides forward into the molded boss in the surface.
Thing is........ if you would not notice an approx. half inch rise under the cushion in the center portion when you are sleeping, such a panel could be used on that E-27. Or a host of other Ericson forepeaks. You could taper the top of the filler gradually of the forward tend, and also about halfway back down each side to avoid noticing the transition with you shoulder blades.
On the Olson the filler just slides forward in the day time.
FWIW, we do
not notice the slight depression at night where the filler has slid out of, so this might not be a problem for you either.
You might want to add some 3/8" guide battens to each side to keep the new slider centered.
IIRC, in the fable, the persnickety "princess" supposedly noticed the pea under a thick mattress due to her royal sensitivity. That was only a story, and how large was the 'pea' anyway?
Cushion support pix are in this blog entry.
Here are some pictures of the project as it moved further along. The next phase will be the upper parts. Color Matching Note: Some years ago when I replaced the factory counter top as part of refurbishing the galley sink, I found that a really...
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