if ya have the bed mounted, here is how I did mine.
I bolted the lower front of the fender to the running boards and supported the rear bottom edge with my floor jack and eye balled the opening of the fender in relation too the tire by slowly jacking up the rear of the fender till it looked right all round the tire and the fender and then got out my tape measure and fine tuned it till I had the same "GAP" all round...then I marked the holes using the fender holes as a template, removed the fender and drilled my holes.
