What was found
(CAN) BEECH 90 DEPARTED AIRPORT AND HAD DUAL GENERATOR FAIL LIGHTS. THE AIRCRAFT RETURNED TO BASE). DISCOVERED THE RIGHT STARTER/GENERATOR HAD FAILED, IT WAS ALSO FOUND, THAT THE LEFT ENGINE SHUNT WAS TRIPPED, INDICATING LEFT GEN FAILURE AS WELL. RIGHT GENERATOR REPLACED (388 TSO), LEFT GENERATOR RESET, AND AIRCRAFT RETURNED TO SERVICE.