I ordered my fuel valve with built-in banjo fittings, with the idea that they would make it easier to route the fuel plumbing within the confines of the selector valve enclosure. Sure enough, it was very helpful to be able to make small adjustments to the angle of of the input lines. After I got everything lined up, I tightened the banjo fittings and safety-wired them in place. Banjo fittings will only pass fuel when the silver nut thing is rotated to a certain orientation relative to the flare fitting, so you don't want them to move around on their own.
Since the edges of the fuel pump mounting plate will be slightly visible where the carpet meets the spar, I decided to paint it to match the rest of the interior. This of course involved removing all the components, which I was going to do anyway. I also put a fresh coat of paint on the selector valve mounting plate, since it was a little bit dinged up. While the paint was drying, I blew out all the fuel lines and inspected the flares for FOD. Finally, I put everything back together and tightened each and every fitting.
I put a dab of torque seal on each fitting to remind myself that I did in fact tighten them, and also to be able to look for loose fittings during annual inspections.
I made a little cover for the selector valve shaft out of some dowel scrap, to keep it from poking me in the ribs when I'm crawling around inside the fuselage. I elected not to put the selector handle on just yet, since it's equally rib-pokey.