Either on the low side of the a/c compressor or straight to the accumulator next to the firewall.........
R134a
you dont only a certified repair shop can handle R12
R12
134A
Freon (R12) has not been installed or produced since 1995.
Answer freon install 1991 Chevythe low side is the big tubing high is small you should look for a siver canaster about the size of a thermus it will have a connection for low pressure to insert freon into system
You don't add Freon as it has R134a not Freon. You add it to the low pressure side which is the larger hose.
R-134a
1lb 10 ounces.
Take it to the a auot shop. you can not add freon
Contains no Freon. Freon was banned beginning in 1996.
you can use r134 freon add a/c oil