I happen to come across a Fiero Store console tray that is supposed to fit in the gap between the radio and shift consoles. It doesn't seem to want to fit in between. It fits like it wants to sit up on the top front edge of the shift console instead of fitting down and in front of it. Is that how it's supposed to fit?
It should fit in front of the shift console. Try this. Remove the ashtrays. Looking inside you should see a couple of screws on either side. Try loosening the screws to allow the shift console to slide backwards a bit.