I am currently in the process of installing my Supplemental Braking System (Stay-In-Play) DUO Vaccum Assisted. The wires and 1/4" vaccum tube can't be run through the firewall without drilling a new hole. I have read an thread posted by DriVer on the forums. He has an excellent write-up with pictures on the installation. I did not see a picture of where the hole was drilled for the wires and vaccum tube. Anyone know where I should drill the hole in the firewall for the install?