Because I'm Restoring a 69 Eliminator, I have asked the same question to my fellow clubmembers here in Dallas. I have been told that the cougar and the mustang package trays will interchange. My upholstry guy has told me however that he could build me one that looked stock that was a much better because of the age and poor condition of my original.
I'm personally going to use the new stock creation from the upholstry shop.
Good luck with yours.:ylsup: :ylsup: :ylsup:
I made my own. Used old one for template and cut from fiber board stock (cheep @ building supply). The fiber board was then coverd with 1/4 " closed cell foam (glues with Dap weld wood) finally coverd with black vinal and plastic screen and stained. Looks pretty good. total cost about $25. I had stain and glue from other interior work.