i can tell you that the BC167b's are hard to find and really pricey, so look for a suitable replacement. i made the layout with the more common CBE pinout so that you hopefully wont have to twist the pins. if you use BC167b's you will have to twist B & C. there's 3 layouts i made for this:
in the DAM reissue of the wah, the is a 47k trimpot voltage divider to control output. i replaced it with a 100k Log, figuring that since that is a commonly used value for an output pot, but you may want to use a 50k Log or play around with the value to get something you like.