[LarryFS]

With the schematic oriented horizontally, I see #21, 8 mfd, slightly left of center.  I see #21A, 16 mfd, and #21B, 12 mfd, on the right side of the schematic.  21A is shown as having a red wire from +; 21B is shown as having a blue wire from +.  The blue and red wires go to the field coil.  The blue wire also has a connection to pin 7 on the 7Y4 rectifier tube.  The green wire goes to a junction of three resistors, items 20, 26, and 36.  I've sometimes found it hard to distinguish wire colors on old radios.  So Mike is correct that you need to trace the wiring to determine which wire goes to which cap.

Larry