i heard about this mod and i am wondering if anyone knows how it can be done? i am using a standard dunlop wah.
what pot should i use and how should i connect it.
links would be also great!

The EZ face has an input cap Blend control.
 This varies how much bass content is 'allowed in'.

hey man.
i am talking about a dunlop wah (gcb-95).

Another way is switchable input caps, of course that uses no pot.
 "Without knowing what 'this' mod is, I thought maybe some suggestions were in order, to help narrow things down.
 Sounds like the description of a simple, adjustable, passive high pass filter, I could be easily be missing something though.

there a resistor that's 510ohms stock and many people change it to 390 because that increases the bass and the gain as well (at least i noticed that).
i am wondering what should i install there?