Help identifying rear quarter glass

[hemibadfish]

I need some clarification on the rear quarter glass on 67-69 Barracuda Coupe. I received a complete order of tinted glass for my 68 Barracuda Coupe. The rear quarter glass I received is not the same as the original glass from the car. The original quarter glass is more or less flat on the bottom where it mounts to window frame. The glass I received is contoured on the bottom with two holes through it, one near the rear and one near the front. I spoke with the glass company and they are saying the glass I received is for a 68 and the original glass I have is for a 67. I thought 67 through 69 were all the same. Can someone please help clarify.

Thanks