I've got 3 guitars with simple New Hartford labels. Those labels were used for guitars that came back to the factory for repair, upgrades or other special attention and differ from regular New Hartford labels. There's a discussion of early paper labels here: http://www.ovationfanclub.com/megabbs/forums/thread-view.asp?tid=52...

The easiest of these to figure out is a Glen Campbell model 1127. The serial number is one of the mysterious M series, M 107. It was sent back to the factory in the early 1990s for a face crack. They replaced the entire guitar and case. What they sent back was a very nice guitar. It is a modern mid bowl, slightly deeper than the original artist, with A bracing. It also has an unamplified UST under a narrow acoustic saddle, not Ovation AE, on a standard acoustic belly bridge. I don't know if the factory added the pickup or if it was done later. The case is a standard black plastic Ovation case of the '90s. It is a surprisingly fine sounding guitar. I knew the factory routinely replaced both tops and bowls on top crack warranty repairs. What surprised me a little was that the neck is consistent with body, but the new bowl may have required a matching neck. It has the fancy Glen Campbell fingerboard inlay and this name engraved on the truss rod cover (perhaps the only piece left over from the original guitar?) and gold plated Ovation labeled Schaller tuners.  It all looks new, but it's now 30 years old. Pretty nice warranty service.

Because of the mystery M serial number, although early, there is no knowing when the original guitar was built. I expect it was after they dropped K from the model numbers in May 1971 but before the 6 digit serial numbers started in May of 1972.  If the original M 107 survived it's run in with the factory and someone has it now it would be fun to know what it is.

The repair paperwork I got with the guitar documents repair and use of simplified rectangular New Hartford paper labels into the '90s.