This mod is a texture revamp of the default P-51D skins within DCS. It is an attempt to bring the Mustang's graphical fidelity closer to ED's latest texture standards.
This is an edit of what I believe the sight would appear like. While I couldn't find images of the real K-14's sight specifically, I have used a number of other gunsights from the WWII era to get the best effect I can out of this.