Hi Mate
Here are some pics of the one I made - Pretty Simple really and not very expensive and looks the goods.
Made from Marine Ply - One piece for the Top then the two pieces iether side Screwed, glued and held together to the top piece using L-brackets and screws.
That lot is then bolted to the floor using L-brackets on the out sides at the rear and insides in the front (4 Bolts).
Drawer is pretty self explantry basically made to fit inc. tracks between to two side pieces
All covered in Marine carpet and just for the extra touch - I trimmed edges with some alluminium strips -
Notice the rear is slanted to fit behind the seats - I did the same to the actuall drawer to so that I don't loose space in the drawer. Also the small cut out at the bottom of the back piece to fit over the Seat Bolt
And in the top view how the top piece cuts in a little for that flush factory fit
All bits bought from Bunnings - expect for the tracks that were from a computer (Server) Rack They are a little pricy to buy
Good Luck