I'm wanting to recharge my AC, but confused on which port to add refrigerant.

Is it label #1 or #2?

 

It's the low side, the one coming off the drier.

​​​​​​Looks like you still have r12 fittings, the r134 stuff from parts stores won't work or fit.

 

That red cap, which is where you'd charge it, may be on a R-134A adapter... pop it off and post a photo without it.

 

It does have an R-134A adapter on it.
Just got the car about 2 months ago, don't know if the owner converted R-12 to R-134A - but *hints* the adapter.. he may have.

 

Doesn't look like he "converted" anything, really... looks like a shadetree kinda just stick the adapter on and pump it full type of a deal... I still see the old factory lines on there. Which of course explains where the refrigerant went.

You can refill it, but don't expect to get too much love from it. For very long at least.

 

I would be tempted to have a shop pull a vacuum on it, and see if it holds..... That will also get out any refrigerant still in there..... Then you can do the R134a conversion, and know it's right.