It should be safe to just import over the top of the old version. I've done it in a few systems. However there is also a DU uninstall which is part of REGI. If you wish to see a video on how to use REGI to do this, there is one here:http://www.saphana.com/docs/DOC-3674
The video is for the Browser IDE, but the general steps shown to use regi to undeploy are the same regardless.