Thanks - one of these came with a bumper kit I bought for my '66 Barracuda - now I know where to stick it!I have one on my car. You can see the back side of it installed in the pic. It fits in the slot in the support structure.
It's just a rubber bumper that the clutch pedal hits at the top when released. That way you don't have metal to metal contact with the support brace. If you run a clutch that requires the removal of the over-center spring, you may not need it.