That was actually a discussion a few of us had at SCR11... Brian Potter has an X11 hugger orange Yenko currently in restoration, and we were discussing how it likely would have been sold when new. My personal belief is that the X11 stripes would have remained, in addition to the Yenko stripes, which would have been up on the body high enough to not interfere with the painted on pinstripes. I have absolutely no proof or verification of this, I just can't see someone at Yenko sanding off/buffing pinstripes... I'd guess the guys who were hastily striping the cars just pulled a stripe kit off the shelf that matched the factory pinstripe color and had at it... then again i could be totally wrong, which wouldn't be the first time...