Hello, Roy! Welcome to WikiTree! You've come to the best genealogical website in the world, in my opinion. Hopefully, someday, you will break through your brick walls. I just broke through one a couple of days ago with very little primary documentation, but I have circumstantial evidence and a large number of matches in Ancestry.com's ThruLines. So my advice is that, if you haven't already, get an auDNA test done. In the case of your Mueller brick wall, a yDNA test might be beneficial, as well. I do not understand very much about the nitty-gritty of DNA testing and how to interpret the results, but there are people here who are very informed about it and would be willing, I'm sure, to give you advice. Best wishes with all your genealogical endeavors!