Nice image, thanks. In the future, you can link to the older post using post #xxxx syntax, using the ID# in the URL (in this case, I found the old post, and it's post #80116).
Then what you can do it click edit on the old post, and in the Parent: field, enter the ID# from this post (i.e. 158216) to make that a child post of this one, since this one is the better image.
