I don't know if this is an obvious thing (clearly it wasn't for me) but if you wanted to treat/coat/paint your transformers, mounting plate and plate chokes, make sure you do so before you mount and wire them up. You can leave them untreated/coated but they will rust a bit. They may also be covered in some residual glue/gunk so having some sandpaper is handy.
I know it sounds stupid but it is really easy to get overly-excited and just get started on the build as soon as possible, and unfortunately there is no warning in the manual about painting prep (probably because for most people it's common sense - something I lack).
Finally if you're gluing the base together you'll need some wood glue. Blumenstein Audio has some screw-together bases that match the Orcas if you wanted to go that route, and the option of adding a plastic bottom window, but they're pretty dear.