Hi,
I am new to the world of building pedals and this is my first post on this forum 
I built a factory kit and mine is also extremely loud (unusable). I've tried as well putting a resistor on pins 1 and 3 of volume pot, but together with the volume it reduces a lot the gain.
So, as all the five pots interact with each others, I was thinking of adding a 6th pot, together with a circuit similar to the volume pedal (https://www.musikding.de/docs/musikding/volume/volume.pdf). Theoretically this would work as a master volume, not interacting with the other five, isn't it?
Sorry if this is a stupid question 