The same applies as with the SS-2, this is designed with true bypass switching in mind, but if you do want to build it with the buffered bypass, then make a daughterboard of the Cornish Buffer. The input socket connects directly to the input of the bypass buffer. The output of the bypass buffer then goes to ODR-2 input and daisy chains to the 3PDT stomp switch, lugs 1 and 4. The output of the ODR-2 will go to 3PDT lugs 3 and 6, and the output socket connects to 3PDT lugs 2 and 5.
The third pole of the 3PDT is used for LED switching as usual.
Info about the original Cornish copy:
Skrydstrup R&D Overdrive ODR-2
The ODR2 is a smooth, dynamic overdrive unit designed to emulate the overdrive sounds of our highly recognized OD50 Tube Amplifier.
This unit is perfect for overdrive tones ranging from a semi-cranked AC30 to the sound of Hendrix.
The TONE control is not a traditional tone control, but a High Frequency Damping control. Turned all the way up the TONE control is not active.