First of all, it is .022 and .047. .22 and .47 are way to high for a guitar. All you would have left when turning down the tone is bass notes.
The lower the cap value, the higher the rolloff frequency and the less apparent effect it will have on highs. If you are just looking to trim off the brittleness, then a .01 cap will be fine. More traditional with a darker tone would be .022, and .047 is darker still. Nowadays, it's pretty much universal that .022 is for guitar and .047 is for bass, but this is an area where you can experiment freely and not hurt a thing.
John R. Frondelli
"Mediocre" is the new "Good"