Expression Pedal Mod for MJM Sixties Vibe?

[gwpt]

Hi,
Just wondering if anyone had done this or knows if it's possible?
I had a look at a vibe schematic (I believe the MJM is a clone, haven't opened it up yet) and there is 250k pot for speed.
As for the expression pedals, I believe the Roland EV-5 is 25k, Yamaha FC-7 is 50k Log, Line 6 is 10k...
So none of the line up...
Does anyone know of any tricks to get around this? Or is replacing the pot in an expression pedal the only option?
Thanks

[joegagan]

ernie ball makes a 250k volume pedal

i don't know much about vibes.

pretty easy to put a 250k pot into an existing volume or emptied out wah pedal.