How do I access the recessed screw in the plastic molding panel on a 2000 Tahoe to change my taillight?

There is a screw that is recessed in a hole in the molding just behind my left tail light. I have tried every common socket known to mankind and cannot lock on to it. Did GM make a custom socket to access this fastener? The closest I come is using an extended thinwall socket, but that still binds on the wall of the plastic recess. Did GM turn down the OD of a standard socket to gain access? Tons of companies do this just to sell "special tools" in the OEM business. If you know the answer, please respond. Thanks to all in advance...Tom