1966 Dart Factory AC Fittings

I am putting together a 1966 Dart GT that has been disassembled for more than 20 years. It had factory AC, but the under-hood components are no longer there. I want to pressure test the AC evaporator, as well as the heater core. Does anyone know what thread the AC fittings that protrude from the firewall are? The larger one appears to be 3/4 pipe thread, but it seems odd that it would be a pipe thread. The smaller stub is somewhere between a 3/8 pipe and 1/2 pipe size.