Nice work Marty. I did a similar fix on the same mirror a few years back, using a fabricated aluminum post and some pop rivets.
I think you'd agree that the key to doing this kind of job is to put yourself in the position of the designer/constructor of the original part, which means having a thorough understanding of the function of each piece in the assembly. A vivid imagination helps too. There is almost always more than one way to achieve the same functional objective, and oftentimes, your own solution will be better than the factory solution because you have the advantage of no constraints on time or money to build a better part. Never mind that it's a 'fix', it's the end result that counts!
