Reduce right side forum width

[Kwak]

Examples: www.webhostingtalk.com (http://www.webhostingtalk.com) and www.sitepointforums.com (http://www.sitepointforums.com)


I want to add an Affiliate box on the right side.
How would I be able to do this on Version 3 beta 6?

[Kwak]

I understand requesting hacking for version 3 is not allowed but is templates okay?