If you are running any version below MR-3, you'll need to manually change the port for the SEPM in the IIS Website settings, and in the SEPM config file. From MR-3 and above, yuo have the option to install the SEPM in a custom website, that runs on HTTP port 8014, and will not cause any issues with your WSUS installation.
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Abhishek Pradhan, MCT
Symantec Corporation