The big "garbage pits" on either side of the main cabin have been annoying me since I got the boat. Set too low in the hull curve to put a book in lengthwise and wasting a huge amount of precious storage space to dead air at the top, plus impossible to keep tidy.
So I finally got around to this. A pontoon neighbour knew where to get supplies here and even offered a ride to a nearby Leroy Merlins (huge DIY store at some shopping center outside Albufeira). Half an hour and some 26 EUR later I left with some timber bits.
I re-used the original sapele bar and made it into a fiddle for the new shelf, so the only part that is visible is original, making it look pretty convincing. The shelf itself is some particle board with plastic veneer. I already had the plywood in hand when I saw this, and it did safe me a lot of time staining and varnishing and days of mess in the cabin (we're liveaboards), so I picked the particle board instead. Marine plywood or real veneer is not available and would probably cost a fortune anyways. The shelf supports underneath are solid pine square profiles (edges rounded off a bit to match the look) with some woodstain to make them match.
Took most of today to do this on both sides, and I'm very pleased with the results. Now the books fit in on top, with a nice extra storage space for all the small bits below. I still have to make a webbing strap with buckle to hold the books in place on each side.