The mystery project took a small step forward today, I drilled the fixing holes, three down the side of each strip, with a 1/2\” recess to take a wooden plug
and in the middle of the slotted side, a hole to ensure the strip stays flat to the surface it is fixed to. This I did by drilling the pilot hole all the way through, then drill a 1/2\” hole from the top to allow access for a screwdriver, after which
using my pillar drill and a countersink bit, I used the 1/2\” hole to access the interior, and countersink for the screw head, in that way the screw wont catch on anything.
That just left them all to be sanded again, now I will cut them to the final length, and stain them, before installation.