How do you remote relay switch but for 2 channels of a pedal?

[KH602]

hi there, am just wanting to know how do you go about using a remote relay but for 2 channels

example - switch between an overdrive or clean signal of a pedal via remote pedal

i know how to make a remote relay to turn the effect on and then off (true bypassed) but not sure about the 2 channels..

it would be good to have true bypass from the 2 seperate channels also if that makes sense.

it kind of reminds me of my marshall mg 250dfx combo amp overdrive & clean channel then dfx on and off.

anyone help

cheers