Test drive it. Does the steering feel normal or is it "squirrly"? A WDH is to put the weight back on the front wheels to regain lost steering control. A nice 35 mph cross wind will help you determine real quick how much steering loss you have.
There is a spec in your owners manual in the towing section. GM says to adjust the hitch to bring the front fender back to stock height. I believe Ford says to adjust it to bring it half way back to stock height.
Ignore rear sag. You will always have some. That's why the truck has a "raked" look.