Finally finished this fantastic beast! Wanted to pass on some items that may be helpful:
• Shipping adds up quickly for component orders - I wish that I had planned better and gotten everything in one or two big hauls. Also, I ordered extras of most all components as backups, and didn't need any of them. Something to consider...
• Tayda seems to be most economical source for majority components - they do not have everything, but mouser should have most of the rest. There are some useful shopping lists around pages 14-16 of this thread that others have shared
• Lay the big cap flat against the board - it is too tall for most enclosures to stand
• Source potentiometers that have solder "hole" contacts - not "tab" contacts - very tedious to solder and probably not as durable a connection
• Use cut leads from components for making "legs" for the switches on control board - see SOMA pics of inside factory build
• There may be an argument for not using IC sockets, but I wish that I had used them, instead of soldering directly to board, as I am curious to try out some different 2399 delay chips for comparison.
• Use small gauge solder for the 2 tiny SOMA-provided surface mount IC’s - .3mm worked well for me
• It was worthwhile for me to get pro assist for case hole drilling - I reached out to a friend who has a millwork shop who knocked this out for me in 10 minutes