Close, it's a 470 that I'm using.
As for the steps, I followed the same route as the OPs directions for FTB; put optifine in the instMods folder, added the files from the zip file for the shader mod, made my shaderpacks folder and put the shader zip file in that folder. Also made sure to replace forge with 518 instead of the default it comes with on the mindcrack pack.
As for the steps, I followed the same route as the OPs directions for FTB; put optifine in the instMods folder, added the files from the zip file for the shader mod, made my shaderpacks folder and put the shader zip file in that folder. Also made sure to replace forge with 518 instead of the default it comes with on the mindcrack pack.