I will do that packing thing when i get a chance to go to staples and get packing peanuts but i think i remember that each sub has its own slot if that makes sense like their walled off from eachother i will check on that in a minute and get back to you and i think if money isnt a issue that 3 nightshade 10 inch with 2000 watt rms each will be enough for my friends to be impressed.
We were thinking of having 2 seats that face eachother or a couch, we have room we just need to get rid of the previous owners dumb mistake to weld 2 rods sticking up to put amps on and place the subs on that which will give plenty of room for more seats. But seats isnt what im worried about at them moment.
Also we were not thinking to switch to 2 15's we were thinking to add 2 15's or 18's if we need more bass, I have never heard real good quality bass in a car ever so 2000w rms x3 subs i think will be more than enough to please myself and my friends.