Originally Posted by c_deezy

I had the same thing happen, and didn't try to fish it down thru the frame. I cushion-clamped it outside of the frame tube, down the boat-side of the trailer. I couldn't see the point of running it inside and having the same thing happen again, on the outside it's not noticeable and is easy to plumb and inspect.

I did have to go under the crossbeams, but I haven't had any issues in the 9 years since I did it.