I don't know why the kits aren't on the website. I've got almost 5 thousand miles on my swap, it rides good and wheels good. I'd give them a call if you are interested in doing it. I have a modified Calmini rear suspension and I do know they were working on their own springs for the rear so maybe that is holding them up. All the parts for my front swap came from them and it has been working really well.
