I had a Toyota 1982 longbed 4 cylinder which I used to haul around my 86 FXR. The back wheel had to ride on the tailgate because I had a toolbox on the rails up by the cab. Never had a problem.
My next pickup was also a Toyota 4 cylinder, but a 1998. The first time I loaded the FXR into the truck, I could see the metal panel on the tailgate flexing, and after hitting one small bump, I found a large dent in the tailgate.
Found out later that the newer tailgates were made much thinner and simply couldn't hold much weight.
Moral of the story: it's not just the cables you have to worry about.