Is this sitting below the waterline, and does it empty past the waterline. I’ve always wondered if that would work. It’s amazing how much water ends up inside the boat after a couple of dives, rough weather, etc.

I copied it following Snapper Geoffs advice. Yes it empties below the water line. He has one each side but I've only installed one because the transducer is in the way. It has a bung on the inside aswell. It goes through both layers of the hull. No Emp, that hideous carpet is in front of the dart board in the garage lol.

Mine doesn't have the keel bungs and since it never took on a lot of water I didn't bother to put any in (this may change though after the motor upgrade). Actually, taking in half a litre of water hasn't been too bad over the last couple of years since it keeps on flushing out sand which is still logged inside the hull. The hull originally was an insurance write off, my mate salvaged it and I fixed it over winter. The gash in the pics above was a crack through the hull and it filled up with tons of sand as well as crumbling the bits of foam in the pontoons. It took me the better part of a day to flush the sand it, but still…
One upgrade i added is a small extension of the hull for the transducer to be tagged on to (pics to follow). The lip on the mac was notorious for sucking in air bubbles making the transducer a bit unreliable while skipping along. Damn, I love this thread, there are so many great ideas. Quite tempted to add the scuppers too…

just a quick update on how the cnc cut floor ended up. Quite happy with it, the swivel seats are great and finally I don't need to negotiate the benches anymore to reach the anchor. If anyone needs the files, let me know.

Thank you! I don't mind if it turns yellow over time, but if you mentioned it because it will become brittle, I'll have to find a solution. Thanks for the heads up. Will a simple Norski PU varnish suffice or do I have to bring out the pricey options?
The pedestals and boxes are treated with UV stable surfboard epoxy, the floor is done with west system. Bottom of the floor is glassed.
The boat is stored in a garage, so doesn't get too much UV- exposure. Initially I wanted to add EVA foam or carpet for flooring, but happy as is

How's that new floor working out e.m.p!
I've recently had the draw bar extended 350mm so I can easily open the rear doors of the vehicle without them hitting the winch post. Also fitted a decent Jockey wheel.