If it was me ,I would mount them so that the outside edge is almost directly below the outside edge of the wood on the transom, pretty much where the bottom starts to flatten out from the round chine. I would mount them about a 1/4" above the trailing edge of the transom.Once your on a plane the water flow is pretty much coming straight off that edge, the 1/4" keeps the tab from dragging. The further out from the centerline allows the tabs to work more efficiently ,meaning less adjustment in the downward direction and that equals less drag more speed.better fuel mileage , as miniscule as it may be.
I shall dub you rivet eye as the reflection in one picture has your mug reflected with a rivet squarely in your eye socket. Speaking of rivets I would mount the outside edges directly below the 2nd [ horizontal row shown ] rivet from the right of the wood transom plate. Also would use a wood backing plate ,not pressure treated, to reinforce tab.
