Fitting a .022mfd would let more treble through than the normal .047, but if you have tried it without a capacitor, then there is something else causing it. The tone at the neck is different to the tone at the bridge because of the string movement being greater, so there is more output from the pickups.
What settings have you got on your amp? If the bass is at 10 this might also be a problem, as the neck will push out more bass than the bridge.
A couple of other things you might want to check are that the pickups are the right way round (the red dot is the bridge, if the dot is not there, then the higher DC is the bridge). If this is the case, then try lowering the neck pickup a bit. I have a neck mule and can get good definition out of it.