So if the CX500's don't have that tab to hold the rear seat down, could you retrofit one onto it? The CX500 Turbo seat appears to have the same hole there for it, but also a couple suction cups, which I don't understand, they don't seem to be in a position to "hold onto" anything? My front tabs on the tank are intact and the seat is mounted there correctly, but the back still has that 1/2 inch space that just looks odd? Thoughts???