That is still a baby truck, there are others that will handle the load even better so why stop there?
$500 will get you a L-Series grain truck you could put a gooseneck hitch on and rip a one ton up oneside and down the other.
You're comparing pickups to semi's... completely different ball game.
if indeed you opted for the big package its overkill for the horse trailer, why would one need a bigger truck?