I finally finished the 4 octave marimba using your make a marimba guidebook for my dauugher on Dec 22, 2009. She gave a little recital for my friend and his neighbors at his house. I can't tell you how thrilled she was and how amazed people are at the sound that the instrument produces. My frined and I really had a great time doing this project. It really cemented a good friendship. Sure, at times we wondered what the heck you were talking about but it all made sense in the end. I included some pictures on the end product. This was perhaps the best $50.00 dollars I have spent in my life. I really believe my daughter has a world class instrument to practice on at home. I can't tell you how nice it is to be able to have her go down stairs in my home and practice a couple times a day.
I still intend to add some side skirts on the corners and some wheels but I'm going to take a few weeks off before a start the modifications.
I did some small modifications to your original plans but nothing too dramatic as you'll see in the pictures. I added two lower horizontal support struts rather than one, painted the angled resonator supports gold so they weren't as obvious, and bought the Musser supports from Century Mallet in Chicago.
Thanks for all your guidance throughout the build. You are quite gentleman and I'd be happy to write a testimonial for you. I can't emphasize how nice it was to send you an email and get a response back on simple questions.