I just had a bit of a scare this weekend. A few years ago, I had done the throttle cable mod to take up the cable slack, and it was great. However, I noticed recently the cable slack came back. I figured the cable was stretching, so I ordered a new one. Good thing for me - the cable hadn't stretched, the spacer I put on had slipped! Sorry, no actual photos - I decided to swap the cable immediately. But I did a Photoshop edit from the tech tip on Mustangworld (http://www.mustangworld.com/ourpics/fcar/99pedals.htm).
How the spacer SHOULD look:
How mine looked:
What had happened was, the cable had slipped down into the groove the image mentioned, and was being yanked at a 90 deg angle. And the cable was breaking.
If you've done this mod, might be worth a quick check to make sure the spacer is still holding.