Korg FK-3 volume to Boss EV-5 expression pedal conversion

[AM]

Hi,

I have an old Korg FK-3 volume pedal and I'm thinking about converting it to a a Boss EV-5 type expression pedal. The FK-3 has a 50K pot and the EV-3 has a 10K pot and a 50K pot as min/max level settings. To use the Boss as an expression pedal one has to turn the 50K pot all the way. It's the 10K pot that is connected to the traedle.

So, Is there a way to do the conversion without changing the 50K pot I already have in the Korg pedal to mimic what's happening in the Boss pedal? (Wire a resistor for example)
EV-5 Schematic attached.