Hi Tim,
Just checked the schematic for the NC-300 here and the power supply Cap is C-62. It is a three section Cap 40-40-20 mfd. Located in front of the power xmfr just to the left looking at the receiver from the front. It is mounted directly to the chassis.
Goo Luck hope this helps, I you need a copy of the schematic I can photocopy it and send it to you.
73,
Fred
EMAIL:
KC1XF@YAHOO.COM