Dont know how your building your stand, if your placing a piece of plywood ontop you will need to drill out 2 holes or 1 big one to fit both out and in lines. The megaflows ar not in the corners like the old days. They are on the back about 5in from the sides. If I recall they measure 10.5" X 5.5". As long as you are using 2x4's or 2x6's you will have enough clearence for the bulkheads. View attachment 145705