I have a 67 mustang coupe and purchased a new package tray and the mounting screw hardware. I have two questions and need some help:
Question 1) The quarter trim panels (QTP) have a lip that extends over the package tray area. There is a factory machined "slotted" mounting hole cut in the QTP lip. I tried to install the tray two different ways:
 Situation A - Placed the package tray on top of the QTP lip. The tray is bowed upward on the ends and doesn't appear to be seated correctly.
 Situation B - Placed the tray underneath the QTP lip. The tray appears to be seated correctly, but the slotted hole in the QTP lip is visible and there is no way the mounting screw will cover the entire slotted hole. There also is a 1/4 inch gap (vertically) between the QTP lip and the tray.
Though Situation B seems to be the correct fit, I can't imagine that Ford would have designed the slotted hole to be visible OR why there is a gap. It almost seems like there should be a trim piece that runs across the width of the car along the back edge of the rear seat to cover the lip OR other additional parts are needed (I haven't found anything offered from any distributor). I can't find any manuals that refer to installng a tray.
Does anyone know how the package tray and QTP should fit together? Are there any other parts needed to complete the install? I know some QTP don't have mounting holes in the lip. Is the QTP I have actually for a fastback or convertable?

Question 2) As stated I purchased mouting screws designed and sold specifcally for securing the package tray in a 67 coupe. I looked at the metal shelf in the package tray area but could not find any holes in the metal shelf where mounting screws were used to originally secure the package tray.
What am I missing?  

I'm not sure if the '67 is exactly the same as the '65/'66, but on the earlier years the package tray was retained by two clips behind the rear seatback and two trim screws with bevel washers on the ends. The end screws went through the package tray first and then into the top of the quarter trim panel.

Maybe your quarter panels are installed too high?

HTH...
Mark  

For it to look right and cover the hole, I would agree it should install as you described.
As for the quarter trim panels - they are installed using the threaded mounting brackets that were welded on to the quarter panel via the factory. Nothing appears to be modified??
If you sit the tray on top of the quarter trim panel (QTP), the tray slopes downward as it runs towards the rear window. If you leveled the tray, it wouldn't fit under the rear window gasket. It would butt up to the gasket or maybe even on top of it.
The QTP are green and that matches the rest of the interior. Is it possible the QTPs actually came out of another style mustang (fastback / convertable) or another year? Is there a way to attach a picture of my QTP to this thread for your review?  

It is possible you have a different year quarter trim panel installed, or some other obstruction. To post photos here you have to have the photos hosted somewhere and then "paste" the link to the photo here. The easiest setup I've seen (and the one I use) is www.photobucket.com. Sign up for a free account, upload your pics, and then just click on the link for "forums/message boards" for the photo you want to share and paste it here...

Let's see some photos of the rear package tray area (without the seat back), quarter trim panels, and so forth...

HTH...
Mark