On my 57 GMC 370 cab forward, it has 2 wheel cylinders per wheel on the front. Are all 4 of these the same part? My NAPA guy has ordered for me and he says there may be different left to right or top to bottom cyls. I have all of them off and tried to keep up with where each one came from, but they got mixed up when I was at the parts store. They all 4 looked the same to me. Thanks.
