How do I go about purchasing the stage 3 kit with single springs?

These kits now come with single valve springs by default, so you don't have to worry about mistakenly receiving double valve springs We can organise the kit via email or you can purchase it online:

http://www.maceengineering.com.au/epages/shop.sf/en_AU/?ObjectPath=/Shops/mace/Products/CCP801/SubProducts/CCP801