Feeding/reaching the vacuum line through the fire wall is not the problem. The connection to the bpv hose will be much easier to "handle" with the intercooler off. I like to electrical tape the line to a straightened out metal coat hanger. (old school mobile audio trick).you must be very careful and do not force the hanger anywhere it does not want to go and work in increments, going from under the dash to under the hood several times until you can safely pull the coat hanger through, success! Good luck!