I tried NAPA last winter, no luck. I got caps from Jimmy Carter's catalog, his are all the same value, and I have one on the ammeter, regulator and generator. With stock plug wires (copper) I have no noticeable noise. The subject is a completely stock 1950, 3600 with restored xxx443 radio, new caps, new resistors new wiring where needed. This doesn't apply to your radio but maybe someone else would appreciate it. I completely disassembled the PB tuner mechanism cleaning and straightening and also disassembled the volume/tone/on off switch and rebuilt it. The radio feels and works like it's fresh from the factory.
Only complaint that I have is, I can only get one local Oldies station and Toronto at night the rest of the time it's just old dudes listening to them selves talking.
Denny Graham
Sandwich, IL