A leaf/link is very simple and I think was first used on the Motown Missle, Pro-Stocker, so that is how old it is. The leaf spring is attached to the housing with a pivot below the spring. Tabs are welded to the housing on either side of the spring, that extend below the spring and are bolted to a pivot that is attached to the spring with clamps. This allows the housing to pivot here, as it is not clamped directly to the spring anymore. Now upper 4-link type bars are added and the front mounts were normally placed inside the upper frame rail, right above the springs. So the leafs still hold the car up, the front segment now acts as a lower 4-link bar and the top bars have been added. They do work well, but if you were going to go to that extreme on the fabrication, why not just add coilovers, replace the front leaf segment with a bar and then you you would have a..............what, a setup EXACTLY like the Unlawful setup. If you have the skills to fabricate a leaf link, you can fabricate your own 4-bar setup like the Unlawful deal and this "bolt on" becomes a moot point.

Monte