Tool for the Retaining Ring?

What tool do you need to remove the retaining ring holding the fuel sender/pump assembly to the fuel tank on a 2002 Chevy Impala 3.8L?

Thanks.

Kent-Moore (now part of SPX) makes specialty tools for this kind of service. I use a combination of a pin punch and hammer to chase the retaining ring around and/or supplement with large Chan-Nel-Lock pliers.

If you really want the tool, you can look here: http://gmspecialservicetools.spx.com/ToolDetails.aspx?id=1786

That's an expensive tool! Thanks a lot Bowtie.