No need to change the jack itself, Tristanpeel. I just connected tip and ring (red and white) inside the pedal. Right at the pot that's moved by the pedal there are three contacts, you can see clearly which one is connected to each cable. Shield is still connected to the brown cable, which is ground. Ring is left open, on a mono jack this would be ground as well. But the TF seems to make contact to the lower part of the jack, where the shield is on stereo jacks.
I don't know if just swapping red and white will work as well. Worth a try but I won't resolder as it works for me.
