[njk53]

We essentially have the same set up on our 71 Chevelle Wagon. We were using the Calvert 90/10 and went to a double adjustable AFCO.
The outer diameter of the AFCO Shock is larger than the Calvert. The lower control arms (LCA) will have to be modified to be able to get the shock between the spring if you go up through the bottom. The AFCO lower shock mount bolt pattern is wider than the stock bolt pattern. We had to machine the lower control arm to trim the stock shock mount holes away and welded the AFCO mounting ring that was provided with the new shocks in it's place. A bit of work but, I think in the long run worth it. If you modify the LCA's for the AFCO's the Calverts will not fit anymore unless you cobble up a mounting scheme to adapt back to the Calverts. As plentiful and cheap as they are, just get another set of LCA's and modify them. So if you want to go back to the Calverts for whatever reason, you can just switch the LCA's.