Repairing Temp. and Fuel gage Indication on a 1969 Dart Swinger 340

Hi All,

Today while out for a nice drive I lost indication on both the Engine temp indicator and Fuel gage at the same time. What do both of these instruments have in common. Perhaps a power supply or a ground connection? Connections on intake and gas tank are all good. Everything worked fine up to this point. What should or I check? I'm thinking its a corroded connection?

Thanks in advance.