Had my 1993 SC300 converted to 134a last year and it needs a little recharge, is the picture below the low side that accepts the refrigerant? The input does not have an "H" or "L" like i'm used to seeing...this input is directly below the passenger side strut tower.

 

both top side and bottom are on the drivers side, at least on my 92 sc4. not sure if it changed through that one year and model.

 

for the sc400..

i believe top is right next to the radiator (driver side) .. should have a stem popping up.. i tihnk thats top..

bottom is right next to the ac compressor..

if im wrong.. switch em around.

 

I've got an Sc300 guys.....not a SC400.

 

just......wow.....