I know everyone was all sad about AF1 intake disappearing act and I was browsing the MAC performance site and came across one of their new products for the 04-07 3V 5.4L. I would assume it works on the 08 as well but it says it has a 3.5" air tube. That's bigger than the AF1 right? Just a FYI to everyone.
http://www.macperformance.com/store/...ategory_ID=495

I've dealt with MAC in the past with my 4.2l and they were hit and miss when it came to customer service so...

 

AF1 was 3" or 3 1/2", you could have either one.