The rear springs may not be achievable as they are proving difficult to re-design. I’ll provide more technical talk at a later date once I have been provided with full details. In short to replicate the Renault spring it’s two different diameter of spring so would need an investment of buying 500 sets in one go., The engineers are reviewing the process....as they are trying to replicate ride height and spring rate in a single diameter coil.
That's a little disappointing as arguably the rears would have a larger market being fitted to a much larger number of cars.
Keep up the great work though.