Sure, I'd build you one w/o subs. Was not that hard to make and I've got the size down perfect to fit in that area. Ya, the storage area....well I still have under the rear seat. Could alway put the amps under the front seats.
I changed out the f/r speakers w/MB Quarts.
Front has MB Quarts Discus RCE 268
Rear has MB Quarts Discus DKE 116
Had to make templates for them to be spaced out, not to bad though. Then Dynamated them to make sure they were dead. "Just drop in"? Not sure , the stock speakers were pretty funky the way they were mounted in the plastic.