Let me start asking more questions and will let you know what I find. Heading out on a trip but will look into it when I return. Thanks again for your help and input on this.From my understanding the TT springs for the 100 series was made for the 100 series and AHC. Which is why I went with that one. I don't think anyone has put non-AHC springs in an AHC 200 series. Will the other 4 different 200 series springs work with AHC? Not sure if they are willing but if you could ask for the spring rate for the 100 series AHC and 3 non-progressive 200 series springs that would be useful.