You need to see what the wires do. Typically one is signal and the other is ground. If that is the case, pin the ground to a fresh spot of metal that won't get hot and attach the signal wire.
If it is signal and power... You'll attach the signal and cap off the power.
Now, personally, I would recommend getting the PCM and swapping the harness. It is possible the two knock sensors operate different logically and will cause false readings.