This has been something i've been meaning to do for a long time. i hate wet chemistry and etching, so anything to avoid it is a bonus for me :)
This is the relay true bypass circuit from R.G. Keen. I've looked it over a few times. i think it's correct. i don't have any relays to test it with at the moment.
i didn't have a schematic to go from - i just reverse engineered the layout that JohnK did. I believe that this is the same as the one available on OSHpark. The way the LED is shown in this layout and on the oshpark board is wrong and if you wire it up this way it will turn the LED on when the effect is bypassed. It would be easy to modify the above layout to do this also if you're using a bi-coloured LED to switch between channels and you want the LED to go between red and green...