I finished assembly on all three yesterday and drilled the vent holes.
For the vent holes I measured and marked a spot 6″ in from the left and 7″ down —- and then 6″ in from the right and 7″ down. These marks were for the pilot hole for the 3″ hole saw. I just bought it and I thought it would be difficult to use on oak. It cut the 3/4″ oak plywood like butter on a hot day. The trick was not to push hard but to slowly move it in and out. Doing it that way helped it to cut and not bind. Can’t wait until these are finished!