I was thinking about doing this same setup, with the Zotac 1070 in a S4 Mini, I assume I could just take an angle grinder to the shroud and use one of the new bezels to get it to fit? On Zotac's website it lists the 1070 as 1mm shorter, not sure if that is measurement error or if they are actually different sizes.The fan mount there is more for HDDs and passively cooled cards. It can work for some GPU setups but air pressure is important.
You could try creating a duct with gaffers tape if your card shroud is too long to be used.