My next question is about heater controls and AC

[jthomass]

I am having trouble figuring out what is going on with the heater and AC controls on this 72 Blazer. Hopefully someone has the same system and can identify what is missing or wrong.
Is the top vent/fan controller with the fan and snowflake on the knobs possibly an aftermarket thing or is this factory? Also on the bottom controller (which is all missing exept the front plate) there doesnt appear to be a place for a fan switch but mounted under the dash is a pretty heavy duty switch.?? I will need to purchase some type of controller.
It looks like there are 2 blower motors with this system, I am going to attach a pic of under the hood also if anyone can tell what is missing besides the compressor. Thanks!

[Burt4x4]

That top unit is aftermarket, probly dealership installed.

Places like Classic Parts sell replacemt parts for your factory controls, the fan switch is one of the sliders..can't recall wich one...years ago I rebuilt mine when I was dayly driving it so I know it can be done

[jthomass]

Thanks. I thought that might be aftermarket. So does that snowflake knob just turn the compressor on or off? And can anyone tell from the underhood pic what all might be missing for the AC components besides the compressor. I know I'll need a compressor and brackets, and my heater control is missing everything.

Thanks