Adding a trimpot to a GGG fuzz layout

[Easywider]

Want to be able to adjust the voltage on Q2's collector . Using a GGG Dallas Arbiter board from GGG , Heres the layout I Used , under NPN , Negative ground : http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=101&Itemid=26#dallas

Is this possible to do ? If so , what would be the easist way to do it , have 100k trimpots on hand , would I have to remove the 8.2K resistor ? , any help greatly appreciated ,

Thanks ,

Chris