Removing Dash To Install Clock????

ok

i got a 91 Civic DX cheapo model and just got a nice factory digital clock off of ebay

i have tried everything to get the piece of plastic that is in the place of the clock out but cant find any screws or anything else. i got the radio plastic console thing off, how does this one come off??

how on earth do i remove this piece to install it: (i have the radio and plastic out but i am talking about the upper part in this pic that also surrounds the 2 vents)



any ideas?

thanks a lot