My Temp Gauge and Fuel Gauge aren't working...

I did a search here and found these are available through NAPA. [URL said
http://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=470&LineCode=ECH&PartNumber=LS6501&Description=Instrument+Panel+Light+Socket[/URL]

Does anyone know if these are a direct replacement before I drive all the way across town?!?
Take a sample with you. NAPA stocks a couple different sizes.