In this first set of pictures, you can see the original posts after the tin was removed. As you can see, the posts leaned inward at an extreme angle. The second photo shows my tape measure hanging like a plumb bob from the new header I was preparing to install. The third photo shows the reason I couldn't remove the second post.
The fourth photo shows the wall with the 2 replaced posts along with the cross pieces that will hold the reinstalled tin. Note that I had to do some fairly unconventional "shimming" to build those cross pieces out enough to keep the finished wall as straight as possible. There will be some curvature to the tin but I wanted to minimize it as much as possible. Remember that on the original installation, the tin was horizontal. I've had to walk on it to straighten it out to reuse it.
The fourth photo shows the wall with the 2 replaced posts along with the cross pieces that will hold the reinstalled tin. Note that I had to do some fairly unconventional "shimming" to build those cross pieces out enough to keep the finished wall as straight as possible. There will be some curvature to the tin but I wanted to minimize it as much as possible. Remember that on the original installation, the tin was horizontal. I've had to walk on it to straighten it out to reuse it.