Adding Reporting Services to an existing SP1 install

HI,

Is there an easy way to install reporting services on a machine that is already running sp1? When I initially isntalled Sql Server I did not install ssrs. Now, SP1 is installed and when I run the setup tool to install ssrs, it warns me regarding a "version change", presumablly because my media is not sp1, but RTM. Any ideas?

1. Install RS from RTM media

2. Apply SP1 on RS.