If I could weld I would just chop the factory rails and put a little gusset piece to make sure its as strong or stronger than factory. I took a good look at it and it looks like you could just cut an inch or an inch and a half out of the portion going down and it would drop the seat where everything should be fine with it moving forward and back and it would blot up in the sae place and all. 1" would be fine for head room, i cant afford Recaro's or Bride's right now which when I can I would like the seats to be slammed so you feel real low in the car.