AC used to have alot of wuality control issues. Their new stuff seems to be alot better. Maybe you got some parts that had been on the shelf for awhile. That withstanding, nothing that I have ever bought from AC or DG has fit properly. AC has pretty good customer sevice these days, I would fire them off an email and see if they will make things right with you.
As an aside, from what I have read, Blingstar is the latest and greatest member to join the club of manufacturers that sell non-fitting fabricated aluminum parts for ATV's.