Factory (dealer installed) air conditioning was offered in the United States from model year 1972 to 1974.  I have owned one car so configured and can attest that the A/C did keep the car cool but it  also sapped the strength of the mighty V4.

A York compressor mounted on the left side of the engine, in something of a mirror configuration to the alternator.  The Condensor and fan mounted in front of the radiator.  As you might imagine, these two add-ons made a tight engine compartment even tighter.  Inside the car, the dash was outfitted with an additional swivel vent and a control panel (a rectangular unit on the left edge of the dash).

The compressor was driven off the balance shaft.  The on/off cycling of the compressor was death to fiber balance shaft gears.  Late in the game, Saab (the dealer) outfitted A/C cars with cast iron balance shaft gears.  NB   Finding an A/C equipped car is no guarantee that it will have a cast iron balance shaft gear. The other downside of this configuration was the loss of the fresh air ventilation system.

The information below comes from an accessory sheet for 97 Factory Air #0262006 and is not found in the standard parts book.  The part numbers are from 1974 and are likely to have been superceded at this point.  Interestingly, many of the components were manufactured in the United States.