I have a 1984 chevrolet with 350. Just recently got the a/c working. I'm using freeze 12 now and it seems to be coming out cold. I need to know how much r/12 or freeze 12 it took it took when you guys filled your systems. I've put 2 cans (24 ounces) in so far and am wondering whether or not i should add a third. Reason i am not sure is because i dont have a high pressure line hookup. Hopefully this is the right forum to post this and thanks for the information.