I found a great model here for another socket extension project, but it did not include space for 1/2" extensions and the 1.5" 1/4" extension I had. The lengths in the original print were a tiny bit off for a couple of the Craftsman 10" extensions so this was built from scratch specifically for the Craftsman product. Figured I'd share! .f3d is attached as well if you need to tweak things.