Track for boot

Does anyone have a good pic of the track that fastens to the rear seatback that the front of the boot goes into?
I'm working on a friends '67 B'cuda and he had the seats recovered but they left that piece off, or lost it. Anyway I got one from a guy that had an extra '68 Dart seat but the part was delivered to me so I couldn't see where it fastened.
Any help is appreciated.
Dallas