As for the bright cap, I wished I would have removed mine. (based on my experience with bright caps on other fender amps) If you use the normal channel or crank the vibrato channel, no need to worry about the bright cap. But if you are trying to use dirt boxes with the DRRI and keep the volume lower, then I would remove the bright cap. The bright cap is only on the vibrato channel and its effect decreases as you crank the amp.
What does a bright cap do? If I don't know how to bias an amp, should I get a professional to?
What does a bright cap do? If I don't know how to bias an amp, should I get a professional to?