More comments on the test results...
First and foremost I can see what I am after in the sharpest prints. They are indeed sharper than my best 4x5 negs enlarged to 8x10. Part of this whole project is a response in my part to a post (here or on LF forum) that an "8x10 contact would be superior to a 4x5 enlarged to 8x10". Always being skeptical, I wanted to see for myself, thus the incentive to get that 8x10 camera working after all these years.
Anyway, that sharp contact print really blew me away, it is really like holding a little miniature of the earth in my hand. It IS awesome and based on this, I am going to keep pushing forward with the project.
Another thing that I think was not clear is that I used the dirty scratched glass to AMPLIFY the problem I am trying to solve. For example, a few dust specs here and there are not going to show up well on a scan to post for your all to see. Also, the randomness of a few dust specs could influence the results. That is, I might get a better result because the few dust specs landed in inconspicuous places in the print, or by chance I got the glass cleaner for one test than another.
But along those lines, I was really surprised by the way the diffused light source makes all the problems go away! I am still amazed at this. It is an effect much more dramatic than I had expected. What a powerful tool (better than Photoshop because its an analog solution!)
Here is another link to the composite image: