I had a Sonic 1 that I changed into a 200S when restoring it. All the screening was rubbed off, and the amp was the same as the 200S anyway, so why not. Anyway, I saw the tag you were talking about Bud, although I don't recall whose initials were on it. It was made in 1970. I modded the circuit a little to get a little better bass response and made a custom cabinet that is similar to an old Sunn 1x15. If you'd like to see/hear it in action, and you're still in the Portland area, you should come down to the Duff's Garage blues jam on wednesday nights at 9:30pm. Let me know ahead of time and I'll bring it. Duff's is on 7th and market on the east side a couple blocks south of hawthorne, and Suburban Slim, one of the best guitar players in portland, hosts the jam. Its a lot of fun! The last time I brought it down there, Conrad saw it and liked it.
Greg