I don't really think it will give any noticeable performance increases but I found it for $60 on Amazon and might want to give it a try. You won't find it on the K&N website under our GT500s but you will find it at the Shelby Store, so I have some confidence that it won't cause any issues.
2 questions please:
What is the Ford Racing part number of the filter Shelby put on an 08-09 KR? From what I understand it's not the similar blue filter (M-9601-D).
What is the proper way to clean and oil the filter? I assume it's by using the K&N recharge kit, but I don't want to assume anything.