It's on "Board 2".? With the radio upside down and facing you, it's the board right next to the two can caps on the left side.? C100 is a tantalum cap almost dead centre of the board.
Note: The K4OAH Service Manuals make finding these parts easy.? I've had them since 2004.? Still available at K4OAH.com from Garey's wife.
