pay little more and get JBA headers. I heard so many complain about fitting and quality issues ... some said not worth it. JBA headers are expensive but it will last long time without any problems.
I think one fitment issue was the header hitting the driver's side K-member, and the fix is to grind or cut some of the K-member. I also think that the passenger side hit the floor pan somewhere - the fix - a sledge hammer to the floor pan.
Hopefully, MAC has been a little more vigilent in thier quality control for fitment issues as of late.