My experience with several different truck/TT and WDH combinations has been that you'll get a feel for the right link to set it at. Some of it, of course, comes from the visual setup but a lot is also just the way it drives. I've found if I set it too tight my rear tires will lose traction on wet pavement when on bouncy terrain. Not tight enough and the chains require no effort to set. If you're bordering on overloading if/when you go too loose the back of your truck will sag. Some trial and error is the best teacher.