Morley Volume Pedal (PVO)

[Unlikekurt]

Hi all.
I have a Morley PVO Volume Pedal. 
I find that the only thing I really don't find to be great about this pedal is the "minimum volume" potentiometer.
According to the schematic available on their site, it uses a 100K linear taper pot to set the "minimum volume" for when the pedal is not depressed.  The potentiometer sets the voltage going to an LED which feeds a detector; when the LED is off you get full volume and as the light increases the volume is attenuated.
In use, you really don't get very much range on the pot at all.  In fact, after some testing I found that the range of available settings seems to be from fully clockwise (95K), which is wide open, to about 60K from which point to full counterclockwise passes no signal.
What's interesting is that it seems that once you press the pedal forward a hair or so past the backstop you start to get into an area with a lot more range, but unfortunately this isn't a place where you would be able to be certain to have your foot move the pedal to with ease.
My initial thought was to change the pot for a linear taper (but now that I read the schematic that might be out).  Now I am considering just putting a shim of some sort on the enclosure itself to stop the pedal from going all the way back.
Any thoughts or advise on this would be appreciated.
Thanks

James