<VV> 64 coupe vent pipes that go into the dash where do they end up and what do they do?

[Ignacio Valdes]

I assume that the 64 coupe black tar paper vent pipes that go into the dash
are for defrost but where do they actually end up? Are they for defrost? If
so where do they vent to the windshield? I am not seeing it on a padded
dash. Also, my lower engine covers were removed by the previous owner. What
is a good source for repairing my heater? -- IV