301 Redirect Simple Products to Grouped Parent in Magento
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I am combining some simple products in our catalog to grouped products.  I need to create 301 redirects from the current simple product pages to the new grouped product page.  

Here is an example of what I have:

 1. Products a, b, and c are similar simple products, each with
    their own url.
 2. Grouped Product z has a, b and c associated to it.
 3. Visibility for a, b, and c are changed to "not visible individually."
 4. Visiting the old link for product c results in a "404 Not Found" error.


I want step 4 to result in a "301 Moved Permanently" with the grouped product url.  I know I can change the entries in the URL Rewrites list manually, but I am looking for a more automated approach.  

Can anybody help point me in the right direction?