There are many manufacturers and race nuts that could sort it regarding extended and compressed lengths and spring rate measurement , trouble is you would need a sample to give them. Glad your happy with the set up Mike and you saved yourself quite a bit fitting it yourself. As mentioned in a previous post ride height is my problem a lot of our driving are on B roads and the Mog just soaks up the bumps, we were out with a mate on sunday he has the SSl front and rear on his roadster and was bouncing all over the place in comparison. Speed bumps are the issue on mine. Em