Differences in 1972 & 1974 AC systems?

[marianamaya]

I have a 72 swinger shell that I am gathering parts for. It is an AC car and I want to rebuild it that way. Unfortunately, no AC parts. What model years can I use for parts?

Can I use my 74 Duster for reference? I seem to remember that there was a change in systems and set ups at some point.

 

[BWDart]

I have a 72 swinger shell that I am gathering parts for. It is an AC car and I want to rebuild it that way. Unfortunately, no AC parts. What model years can I use for parts?

Can I use my 74 Duster for reference? I seem to remember that there was a change in systems and set ups at some point.

I believe they changed in 73 I have the a/c heat unit from my 72 if interested pm me

 

[Sedanman]

Here is a pic of a 67-72 system and a 73 and up switch. The last pic is the 73-up switch