Just me, but unless you know something about structural engineering, steel yield strength, size and shape of framing members vs. twisting moments; I would be very leery about adding a hitch to any 5er that didn't come with a rated hitch. You may very well be using up all of the built in safety factor when you tow something. It could be one of the most costliest mistakes you ever make. And if your 5er is called an "Lightweight", "Ultra-Light" or any variation, you're playing with fire if you ask me. They ain't making frames like they used to, it's all about light and cheap now.
