I am including all the related parts from the custom-built amplifier using a pair of 4-400A's this came out of.  You get a very nice vintage turns counter and a right-angle drive, allowing you to mount the capacitor vertically on the chassis.  The capacitor itself has plenty of range to cover 1.8 - 50 MHz, and the voltage rating will handle a Legal Limit++ amplifier.    Full proceeds from this sale will go to charity - thanks!