As I mentioned, I've been using your upper spring perch adapters to run 70-mm straight springs in the rear of my NC. The 70-mm springs give me extra clearance to prevent rubbing the damper. In order to fit the 70-mm springs, I epoxied some carefully chosen hubcentric rings to the OD of the spring seat. Unfortunately, I still get a little rubbing between your adaptor and the damper.
So, would you be willing to offer a set of your adapters designed specifically for 70-mm springs, in other words machined with an OD of ~69.5 mm and and ID that's ~5 mm more than your current model?
2009, STR & DD. 1995, HPDE. 2004 MSM, sold. 2010 Mazda3, hers.