Need help reversing the polarity on an ORP probe

[tigé21v]

I'm looking to reverse the polarity on my Milwaukee ORP probe, I want to use it to control my sulfur denitrifier. Though I've seen it mentioned many times, I can't seem to find a step-by-step. Is there an adapter available, or do I need to buy/make a jumper cable? If I need to make a jumper, can I use the wire from an old ph probe?
Any help is appreciated, thanks in advance.