Mostly solid advice here. The only thing I would add is that if you do the "zoodad mod", (which is simply cutting a hole in your inner grille to allow more cold air flow to AF), you also make a small block-off plate w/ thin plywood to drop in front of hole when driving in significant rain.
I have the zoodad hole and recently drove through a massive thunderstorm in SD for an hour or two @ 70+ mph. My AF got absolutely soaked, (at least the front of it), to the point where it moved my filter minder. This is with a brand new OE filter.
I'd stick w/ an OEM Ford filter, as others have said they can last forever in non-dusty conditions. They are ~$100 list but I found mine online for under $50 including shipping. Some of the knock-off filters are OK but supposedly not as good as the blue ones. Considering the role of an AF on our engines and how infrequently they need changing, it's a bad place to scrimp IMO.
