I'm sorry to have to report this Joern, but yes, your trim tag is a reproduction (aka fake). The L78 engine wasn't even available that early in production, and like Mike said, when it became available later in the model year, it was only available with the HD 3 speed or the Muncie 4 speed. And more bad news. Your car didn't start out life as a big block. Only small block and 6 cylinder engines were available during tht time frame.