interior leak!!!

Same Problem I Talked To My Dad Either A Cowl Vwent Leak Or Heater Box I Taped Up My Cowl To See If That Helps If U Want Tape It For Now Then Spray And If Not Its Prolly The Heater Box But U Can Try To Spray Air Through The Lil Lines In The Cowl Might Work Fixed My Dads 67cud'a