Distributor hose routing help

Oh, so you think there's a hole in the diagphram or the housing?
Is there a cap where the red line attached?
Could put your finger over it to verify the connection since you suspect the hose.

As far as a new Vac module. See what is suggested in the slant six subforum here and there's a couple bulletin boards dedicated to slant sixes. Maybe search for OSAC delete with Vacuum advance.