Or.. you can install the 4 disc storage compartment that fit into 1-din size. you can ask your installer if they have it - mostly scavenged from stock cars that upgrade to 2-din headunit. Last time i used Perdana 1-din compartment below the 1-din headunit in my ex-kenari.

i'm not that keen on using 'number plate' to close the hole as the plate is shiny and not 'ngam' with the dash colors.