I bolted a piece of slotted angle to the inside front of the tub surrounding the tank. Bolted a Z shaped piece to the floor behind the tank. The z shaped piece was made by welding 2 pieces of brick lintel together. Bolted a piece of 16 ga steel on top of those which made a platform to bolt the seats to. The Z shaped piece is just the right height to clear the tank filler neck and also give seats a flat platform to sit on. It could all be removed later with only a few holes to fill all in a relatively invisible area.
