ford have it on a couple of year on mustang but strut tower are built for it and approved by companyThe only thing I can say is to crawl under your RS and find the adjustment points...There aren't any for camber, front or rear.
The Ford tech confirmed that there is no way to really set camber. He said that on some cars (not sure which model) that they'd drill out the upper strut mounting bolt holes so they could shift the tops of the struts inward (more negative camber). But on the RS, even if you wanted to go thru the hassel there's no space for the springs to move. Regardless of the Ford spec there just isn't any appreciable camber to be had with a stock setup. If someone else has any hands on experience I'd welcome the input.