Our cars always get air through the doorseals.
The advantage with the control I have is that it is a climate control. You just set the temperature you want and it will adjust the fan speed and compressor to reach it. When the temp is OK the fans slows down. When the interior gets to warm again the AC turns on. Just like modern cars do.
Here is an old thread about it:
https://lateral-g.net/forums/showthread.php4?t=9220
I connected an rotary switch selector to control the doors in the VA box.
Jan