Well, Michael, I have had this STC in my possession for over two years. I have gone over and over it many times. But this is the first time I "saw" this "Snafu!" And that is exactly what it is, an accidental ommission of the A150K to require these placards. Unlike the L and M models, the K model is specific to a single year of 1970. With this ommission of the A150K, the placards are not required, and the aircraft maintains it's "Utility Category." Thus it looses none of it's previous certifications.
Anyways, that is my limited thinking where the law is concerned........
