Ok, lets clarify a few things.
The Red Eagles were only on the earliest Std Autos & early MKI's. That eagle was recessed & red with a silver background. Alex Sturm created it, and he died in 1950. In respect for his friend & investor, Bill had the color of the eagle changed to black. The earliest black eagles were in early 1951. Production medallions did not have red eagles again. The change to silver eagles AND them being raised, came about in the mid 1970's. The background was black. Then in the 1990's the BACKGROUND was changed to red. And since then, they have re-introduced the recessed black eagle, and changed the background color on some models.
Original red eagles stopped in 1951.