Hey Lex.
Just found your build thread today and love all of it!
I figured out bag & tag in the winter of 1989/1990 when I rebuilt my first engine—a 1200cc motor from a 1963 VW Bug. Every nut and bolt went into a ziplock bag, the bag got labeled with the part the fasteners came from, and then the bags were poked and slid onto a wire hanger I opened up.
Assembly was in reverse and nothing was lost.
Today I am a Continuous Improvement/Lean Coordinator, who is especially passionate about 5s. 5s appears to be in your genes too. If you don't know about 5s, you will be blown away when you Google some images of it. I just did, and there was a picture of your living room work area!
Ben Franklin once said: Treason is a word invented by winners as an excuse for hanging the losers.
My twist: OCD is a "disease" made up by the messy as a way to marginalize the tidy.
You don't have OCD. You have a gift. You 5s well. It's something you do, my Mystery Man. You're an all-star. Keep breaking the mold!