How to line up the pieces at the coast near the shipwreck?

In The Witness, I was walking along the coast, and I came upon this:

Now, since I've learned

that mazes can be embedded in the environment,

I see the puzzle here, but I just can't get the pieces to line up well enough. Standing on the couch and walking all around it doesn't seem to get me a

functional maze.

Where do I need to stand to activate the puzzle successfully?

When you stand in front of the couch, the pieces will line up to make the path.

This is the correct position; however the starting-circle has a rectangular gap, and a large chunk of the path is missing...

Hint:

There is something orange and movable that can fill in the gap.

Solution:

Set the boat off on its own, then run back and wait for it to pass by.

Take a look at the other end of that piece of metal. It's not round, you can't end a puzzle there. But you CAN end the puzzle on the piece of metal a bit further over. You'll need something orange to bridge the gap.