Is that the "z" shaped metal that attaches to the back of the fuse box and allows a lot of relays to be mounted? If so, I have a couple of them.
Nope, that is correct for the 68's
I only had a picture of this bent one handy to show...I can update again later if need be with a better image.
This shows the arrangement or the Convenience Relay, The Tilt-Away Relay and the Fog Light Circuit Breaker, taken from an October 66 Detroit build, if ever found to be of important on "details" (build data is as memory serves, not necessarily exact)