Ok, so it took me over a week. i got sidetracked with modding my dark mechanicus ogryns.
Here's a pic showing the factory in relation to 40k models. It works really well and i plan to use it in games, although its fairly fragile.
I'm planning on making similar style sheds and factory structures for my siege of Acieris Terrain board. They will be more 40k though, symbols and big machines and what not.