I just read in the Chevelle restoration book that three different hinges were used in 67
. It says the part numbers for a replacement hinge are 3910667 LH and 3910668 RH. Supposedly they cross reference with 65-67 Chevelles,65-67 Impalas, and 66-67 chevy IIs.
I don't know if this helps or makes it even more confusing.