Any good methods/ideas? Next on my list! The springs are rusty so will soak in Evaporost to start...

I started with pretty clean regulators to begin with but I used evaporust as you are doing. Then made sure I cleaned them off very good. The evaporust to me seems to leave a residue and seemed to me to freeze the mechanism up after soaking and drying. So make sure you lubricate everything really well after soaking and everything is free moving before you install and button up. Hope this helps.

Scott