They weren't FAQs but sheets that called out each and every change from the many v1 army books to the two v2 theater books. And yes, it is indeed be a hassle to go through item by item and modify the old books to bring them up to the new standard.
Anyhow, as Hordak mentions, if you are playing the U.S., the only mid-war book you need is "Afrika". It covers all of the US forces as they fought in Morocco to Tunisia and also covers their actions in Sicily and Italy in 1943 (as well as the Brits, Jerries and Eyeties).
And yes, if you weren't eligible to get the free A-5 sized v2 rulebook (by having already owned the v1 book), you will need to purchase the rulebook as well.