Ford (Edsel) Condensor question

I replaced my voltage regulator on my 58 Edsel this weekend and there was some sort of condensor connected to the "arm" post of the regulator. This was about twice the size of the condensor that went in the distributor. Any ideas what this is? I went to NAPA to get a replacement today and they didn't think they had one that big since they'd never seen one of that size before. Any help would be greatly appreciated!

 

all it does is help keep the noise down on the radio,not essential for charging.