I want to paint a 1985 firebird, flair tint violet. how many ounces should i use? or what should i do?

well. to add a lil more detail. right now i just got the body and paint done. the body was done nicely, but the paint was good except for detailed areas, like door knobs, etc... its black, should i just spray a flair tint violet over it? i dont want it purple, just a hint of purple. idk.