[Dave Hirshberg]

Bill,
One method is to clean out the existing holes and fill them with west system,decking putty,reinforced polyester putty or whatever you are most comfortable with, then redrill the holes to fit the 1 /4 brass drain tubes. Once flared those tubes are far stronger than PVC. You will have to clean out the holes first with a die grinder with an aggressive bit. and I would reccomend grinding out some circular grooves inside the holes to keep the epoxy/filler material from slipping out later-on.