Installed my Hellwig bar myself in about 1.5 hours. I am only a basic (easy stuff) kind of mechanic, so if you have the tools and can read the general directions you should be fine.
Your picture looks a little low in the rear. My F350 looked the same until I installed Firestone air bags.
Between the bags and the Hellwig, the sag and sway issues have been reduced to where the ride feels smooth, with minimal sway and the truck sits level with only 28# of air in the bags.
Good luck and keep us posted.
Lakeside