The capacitor value is essential for this type of modification, so I really recommed to get a 1.5 or 2.2 nF (nano farad) cap. I'm not familiar with the data written on the different caps of different manufacturers, so I don't know what value you have now.

The resistor is not the most important component in this setup, and its value is less critical. That's an important difference to a standard tone control circuit.
Let the thunder roll and the lightning flash, I'm doing alright for country trash.