This model seems to be modeled after the art work from the back of the "Fugrim" book in the Horus Heresy series where he is dueling with his brother Ferrus Manus over the corpses of both loyalist Iron Hands, and traitorous Emperor's Children amist the carnage of the Istavaan V dropzone massacre.
http://www.blacklibrary.com/exclusive-products/fulgrim-poster.html
Courtesy of Apocalypse 40k blog.
The first photos of Fulgrim from the Horus Heresy Weekender program.
And here is the complete instruction sheet.
http://www.forgeworld.co.uk/downloads/product/pdf/fulgriminst.pdf
Loken