Yep. No idea why they have been complaining. I have a 240, 260, and both 280 styles available to me. Only difference I can see is between 70-76 and 77-78. That difference is in the location of the door lock pull. On a 77-78 door panel the door lock pull is a few inches forward. Since we are not concerned about this area when replacing the cardboard section of the panel, this is a moot point. There is also differences in location of the holes for mounting the door handles but since you are not drilling the holes and this is the responsibility of the person mounting the panel, this is also not a concern.
Joe