hi mate, if you decide to have a crack at making one yourself feel free to ask questions. It really is a piece of ****. Basically its a sheet of 2mm alloy. Lay the bumper on it and draw round the bottom lip, Draw an identical line 2" further out. and measure back from the leading edge of bumper to just past where the bulkhead meets floor. This gives you the depth. Then i cut out for exhaust and clearance for the wheels to turn. I welded some pieces of box section with plate on the ends which i tapped on to the rear of the subframe to accept the rear of the splitter. Then i mounted the front of the splitter to the lower intercooler frame etc. This was held with rivnuts. I used alloy angle to make supports and to bolt the upright part which can be seen in the pic with large rivets holding the two pieces together.