Stock sway bar or Aftermarket?

You may want to check that out. IIRC, ADDCO made two front bar diameters for the 67-72 A-body. The larger diameter is 1.125 in diameter, the smaller is 1.00 inches, same as stock. You also may want to check out the distance between the "eyes" on the ADDCO bar. If the distance is the same as the stock bar, great. Some of their bars required the use of flimsy tabs that bolted to the lower shock mount. Ugh!