Two builders plates?

I recently acquired a 1970 O'day daysailer. On the forward air tank there is a builders plate. It lists the hull # as 22131 and the class # as 4091
Under the back deck I found another decal with conflicting information. Anyone have any idea what this second label is from? Hull Number 030-22-nnnn from Diamond Antenna and Microwave Corporation, Winchester Mass. (number and photo removed - see below)
I Googled Diamond Antenna and Microwave and came up with the following:
Albert S. Hovannesian founded and served as president and CEO of Diamond Antenna and Microwave Company, conducting important work with antennas and radar.
Was Albert (or some else with the firm) a class measurer in the mass. area and this was a way to log boats that had been measured? I don't know much of the history of my hull but I know it has not always been in Calif. There is a shadow of a different state registration.
Under the back deck I found another decal with conflicting information. Anyone have any idea what this second label is from? Hull Number 030-22-nnnn from Diamond Antenna and Microwave Corporation, Winchester Mass. (number and photo removed - see below)
I Googled Diamond Antenna and Microwave and came up with the following:
Albert S. Hovannesian founded and served as president and CEO of Diamond Antenna and Microwave Company, conducting important work with antennas and radar.
Was Albert (or some else with the firm) a class measurer in the mass. area and this was a way to log boats that had been measured? I don't know much of the history of my hull but I know it has not always been in Calif. There is a shadow of a different state registration.