need space fore 6/9s for 626

i put 4 roxford 10s in my trunk@ 1000w each. its a bit mutch but i can dround out the rap in the car next to me with a nice dose of ac/dc:D . the problem is my 6" speackers wont cover that bass. could i cut the holes bigger to fit 6/9s whith out any problems? :ylsuper