[wbs]

thank you very much gdmn and fundy- ur pix have helped me 200% to see what i need to do- i have put a couple of books on front riser tabs to simulate the board-then the spring base fit within the front riser- i have slid the ledge of the back riser 18" from the front finally i trimmed the ends of the rear riser so thathat it fits between the sills i have attached a pix but its not very good whoops i dont see how attach my pix