Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Usually the high side port is on the thinner pipe and the low side on the thicker pipe.
You have to vacuum the system, too before you add R12. I assume you knew that.
Let me see if I can find some pics or diagrams. BRB.
One is on the accumulator and the other on the tube coming from the accumulator.