There should have been an About PDF in the Developer folder that details how to uninstall the SDK, which mainly revolves around how to use the uninstall-devtools tool in Developer/Library/
Use of uninitialized value $dir_name in substitution (s///) at ./uninstall-devtools line 153.
Use of uninitialized value $developer_dir in concatenation (.) or string at ./uninstall-devtools line 118.