JW I'm jealous. Some of those Harmony Soveriegns were excellent. Never played one but I have a 66 Harmony Bobkat I like fairly well and have played a bunch of other models over the years at pawn shops and such. The Sovereign was probably the best one they ever made. I don't know where to find the date on that one, my Bobkat is a solid body and the date April 1, 1966 is ink stamped on the back side of the pick guard. Look inside with a flashlight, and under the pick guard if you can see under there, it might be stamped.
Many people don't know the true Harmony guitars were all made in the US and they made their own body styles, never a copy. After they folded a Japanese company started making Harmony guitars to make money off the name, but making copies and with a headstock Harmony never used.
Here is one of the Japanese "fake" Harmonys.
http://www.ebay.com/itm/Harmony-Electri ... 1133204267
Look at the 3rd picture, just the headstock, they also never put that "EST 1892" on their logo. That guitar is not a true Made in USA Harmony.
This is the guitar I have, with the same DeArmond Humbucker. Mine is a little more beat up...got it at a yard sale in San Antonio around 1997. 2 bucks...a dollar for the 3 missing tuner grommets, new strings and a bit of TLC and I used it at band practice last week.
http://www.ebay.com/itm/Vintage-Harmony ... 1121335822
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