Thanks for the info on the cardboard spacers!
1) As for the mounting screws purchased - they are trim screws and I assume they are to be visible once the tray is installed. To clarify see -
Mustangs Unlimited - The Source for Mustang Parts, Shelby Parts, Cougar Parts and Accessories
I have the brackets that clip onto the front of the tray. Looks like the brackets were originally secured with a clip and I replaced the clips with #8 screws and quick nuts. Since there was no threaded hole in the metal shelf, I can't figure out where the mounting screws purchased are placed?
2) Since the QTP sets on top of the package tray, how do you cover the slotted hole in the lip of the QTP? There isn't a screw that would cover the oval hole. It also seems like the lip should be covered. That is why I first put the package tray on top of the QTP. If you need a pic of the QTP, let me know!