I own, but have not yet had the chance to play, Achtung! Cthulhu 2d20. I also own, but was able to play once, the Savage Worlds Achtung! Cthulhu. I have Pulp Cthulhu 7E, but have so far only played normal Call of Cthulhu 7E and not played it with Achtung! Cthulhu. About how many sessions do you expect 'Assault on the Mountains of Madness' will take to complete once you have a group of characters together? I could do Central Time Friday evenings (if this is a short campaign and you can find some others interested in giving it a go; one PC does not make a group).