Do you have a Factory Service Manual yet for your car ? It answers most of the questions that people ask on this forum. They are a free download.
383 a/t heated air intake system Holley # R4668A
" " fresh air intake system Holley # R4735A383 a/t
or if Carter equipt
383 Carter # AVS-6125S
According to my broadcast sheet decoded by Galen mine is R4667A 71 383 4spd built in September 70 with the wire to the electric vacuum advance, I searched for years to find one.