What will make 1973 Dart rear package shelf black again?

I have a repop I bought from an unnamed company that was supposed to fit my Dart Sport. It is way too big and I suspect it fits a Swinger. They were weenies and won't admit their mistake and won't take it back. I'd be happy to sell it cheap. It does me no good and is gathering dust. We would have to measure to make sure it fits if you want it. I don't want to send you an unusable part too. I actually have two that don't fit my Dart. I finally made my own. Hardboard and black paint.



What's involved in removing it and what are the dims of your shelf?
Thanks,Greg