Probably obvious, please forgive the comment, but with greenhouses it works to mark up every bit with every adjacent bit in all directions. Different colours, arrows and numbers. Plus taking photos at every stage with the markings showing on the photo or a good sketch with the markings, because there is a chance that the dismantling and the re-erecting do not happen within a day or so of each other.
Good luck and hope it all goes well. Stay safe too