Question about 1969 Barracuda door lock button

If that is a visible screw it is a 67 door, if it is a plug and the lock is at the back it's a 68 door if it's a plug and moved forward it's a 69 door.

As you noted it is very likely the 67 to 68 and 68 to 69 had some mixed parts.

67 parts book shows 1200 67 Darts got a press on speedo cable.

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