How do these disconnect? I'm removing my dash to change my heater core. I can move it far enough without disconnecting the wire blocks behind the kick panel with the bolts through them but I could move it further out if I could disconnect them. The one closest to the front just comes off once I remove the bolt but the once behind it will not. I have a hard time maneuvering my hand in there to pull it apart but I'm pulling on it harder than it should take already. There's a tab but I can't tell if it gets pushed in or pried out. Does anyone know?