Try this, take an old parking sign, cut with a jigsaw to the shape you want. Next take an old Persons, Troxel, or whatever and remove the springs. Where the front spring ataches to the seat frame grind you a slot in your new seat pan and slide your frame into it. Now just mount the rear of the frame w/carriage bolts, slap on some foam and cover w/ your favorite leather. That's what I did on my Boardtrack project because I couldn't find a seat that looked low enough/right for my frame set-up. You know there wasn't any springs on those old bikes! Hardtails forever/ suspension never