Rear hitch cargo boxes and stern lines?

I have a Betsie Bay Recluse, which measures 19’2’’ along with a Betsie Bay Valkyrie which comes in at about 17’ and have a question about transporting the kayak along with a rear hitch cargo box. For my stern line and no box, I connect a rope from the kayaks’s stern to the safety loops welded to the side of a Curt 2’’ tow hitch receiver. This has worked quite well for me. Now I wish to attach a Thule Arcos rear hitch cargo carrier to the hitch receiver. The problem is that to connect a rope from the kayak’s stern to the hitch carrier’s safety loop, I’m going to have to pass the rope either over or under the cargo box, which I’m afraid will stress the box and/or the kayaks.

Note: I don’t have enough space to carry both kayaks on the top of my vehicle along with a roof top cargo box.

So the general topic is how to attach stern lines when using a rear hitch cargo box.

Keep in mind that bow and stern lines, as well as the primary straps, need only be snug if using lines that don’t stretch. They shouldn’t stress either the boat or cargo carrier if tensioned properly.

Avoid ratchet straps, which can easily over-tension straps and open hooks on bow and stern lines which can bounce loose.

You’re telling me, I saw a guy with a Jeep and a P&H that he had ratcheted down using ratchet straps, that boat no longer had a rocker of any sort, in fact if anything it was reversed rocker.

That was a clear case of it’s not going anywhere… Even if you roll the Jeep.

Of course the boat is pretty much shot, but it’s not going anywhere that’s for sure.

Attach them to the cargo box.