Hey Jeanette! You are very welcome! I have used a piece of leather and vice grips to encourage the adjustment screw in the past. If you're gentle you won't mar it. I'm glad you got it moving though!
Out of curiosity, does the plate match the throat plate, or is it like the ones for the 99/66 machines that fit but the finish is satin instead of chromed or nickel plated? For the difference in price, you made the right choice. If the other plate was maybe half or less, I might have considered it and tossed it in some evaporust to see what it would do. That said, sometimes it's nice to sew rather then fight with beat up parts.
I'm not smarter. I'm only a little further down the path. You'll be right along side me very soon, especially with your son helping you out too!