The typical method is breather on passenger side with a tube to the underside if the air filter cover and a PCV valve on the driver side with a tube to the front of the carburetor. This will properly ventilate the engine. Make sure all other vacuum ports have new plugs for a good seal. They get brittle and leak overtime.
chevy runs deep, Don't step in chevy!
67 Coupe 289 - TCI C4 w/2k stall; Holley 4150 570cfm; Performer intake; mild cam; Pertronix HEI; 302 heads; Roller Tips; Hedman Tri-Y headers; H-pipe w/Flowmaster 40's; 9 in posi 3.50; 205/50-17F; 225/50-17R.