We had a Mandal headboard in our original bedroom and with a baby arrival we built a new bedroom and our bed is now near a corner.
First I cut 3 60 cm length iron bar, similar to the ones that assembly the wood.
I screwed them onto the wood bars, and replace the original bar on the longest piece.
I cut the headboard with a circular saw and sanded the ends. One cut is with 45° angle and by reversing the top with the bottom, I had to cut only once by 45°. The other cut is regular.
Then I had 3 pieces of Mandal headboard and fixed them on the wall.