Bubber,
Your soul grinder is fantastic! Love it.
I'm also trying to create a Nurgle soul grinder...
http://www.dakkadakka.com/dakkaforum/posts/list/229684.page
To the
OP...
Remember you want decaying tones. Base coating with a lighter green and using purple glazes or washes creates a particularly disgusting look.
Just don't use the complete palate for the green armour as green
IMO, otherwise it will look too nice (even if you use a black wash).