Ok Rob, here is what I have. These do not seem to be 100% correct all the time. Of all the clips that I have, there were 3 different shades of blue, two of green and the colors did not always match the size. I think suppliers may have had a lot to do with the inconsistancies. All my clips are from 1970 Chevelles and these are the most common colors I came up with per size.
3/16" olive drab (brake lines)
3/16" blue (fuel lines)
1/4" Yellow cadmium
3/8" blue used on either
These are the solid end type clamps.
The double strapped end clamps that I have are both blue and green. Then there are the double line clamps. I have some of these in all three colors.
The rear steel clamps for the fuel and brake lines have for the most part been grey phosphate though I have also seen some that are black. These are the two clamps mounted to the rear of ear side of the frame before the rear crossmember. Hopefully this helps and does not confuse you more.
Rick