Hi Shady Sadie
The original Aerokits plan which I have a copy of, only shows a rubbing strake at the edge of the deck/side as 1/4" x 1/8".
Personal after my SG&K 1920 Gentleman's Runabout which did not have spray on the bottom of the sides(not invented in 1920).
I would be adding spray line as the runabout throws a mountain of water up the sides at low to mid speed and on cornering.
Looks great, but, the boys keep their boats out of the way!!!!
As for spray rails on the bottom of the boat, two on each side as it help lift the boat out of the water for more speed.
Added a picture of my experiment on a Swordsman hull to give you an idea.
Canabus