Speedmaster Stainless Rocker Arm Issues

My last LA builds used Hughes and T&D rockers and I shimmed them as necessary, so I am well aware that rockers are not just a bolt on and go item. However, I am just wondering how much "shim" per say is needed with these rockers and a dual valvespring setup, as I see it there is a big difference in shimming for geometry vs shimming for interference..
I sure like beehive springs for that reason. A friend bought a set of those rockers and they were a long ways off on his Edelbrock heads. He ended up with Hughes and I think without shimming. His issue was alignment and not spring/retainer interference though. Makes me wonder how good the Edelbrock rockers are their own heads.