Lich Bane and/ or Nashor's on AP Kog Maw?

So I was theorycrafting some AP Kog builds, and was thinking about a more AP Marksmen focus. Of course, the Pure AP + Poke Kog build is the most prominent right now, but I was thinking that if you're up against a team that you can safely auto attack as AP Kog, then building Lich Bane and potentially Nashor's could give Kog a LOT of sustained damage.

The standard build for Kog right now is Tear -> Luden's -> Sorc Shoes -> Finish Seraph's -> Void Staff -> Death Cap -> Liandry's, but I think you could pretty easily replace Liandry's with a Lich Bane (which is good if you can auto attack often enough to proc spellblade on cooldown); if you're going for more of an auto attack focus, you could replace one of your other items with Nashor's, which would give you INSANELY high on hit damage (plus, with 20% CDR, plus runes and masteries, you could easily hit CDR cap and have almost 100% uptime on Kog's W).