Looks like you may be missing the plastic covers and sensor rings (brackets). Here is a list of things I needed for the bumper I got. End Cap Bolt = "Bronco" bolt.
You could buy a black top and take it to an upholstery or canvas shop. They could deconstruct it to make patterns and make a top in any color you want.
If 4L/7th gets you to 70kmph/43mph, then 4L/10th will get you to 110kmph/68mph. What's the target? If it's still not fast enough, 4H with lower axel ratios are needed.
A 1" narrower tire will only move the shoulder of the tire in 1/2". Also, the stock Sas tires run narrow, so you may not notice a difference going to a 285 that runs wide.