Condensers (capacitors) are electronic shock absorbers. The most important noise filter for an AM radio is the one for the generator armature, and it should be installed right at the ARM terminal of the generator. The other important source of RF noise is the ignition coil, and the condenser needs to be on the coil mounting bracket. Most original equipment coil brackets have a raised mounting point with a screw hole in it for that purpose. Make sure the noise filter condenser is connected to the (+) side of the coil. If it's attached to the (-) side it will cause metal transfer at the points, and it won't filter RF noise.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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