Putting together my new rig. I have a 16 AIAT and just got a gen 2 Razor 4.5-27. I plan to use a Spuhr 1 piece mount but am unsure which is proper for this rifle. I believe the AT has 20 MOA built into the top rail from the factory so I am pretty sure I dont need anymore in the mount but please confirm. Also what height works best with the AT? It looks like they come in 1.1", 1.3", 1.5" and 1.7" heights. Thanks