[Troy_Audio]

You could always leave the front(nearest to the front of car) open
add some acoustic foam to brake down the standing waves.. thats kinda what i did . my Alpine Type X need lots of air aswell..
They sound good for now my imaging is off a bit but I think a good tuning will help alot..
the 1 thing you want to avoid is air from behind the speaker getting to the front ..this will make cansolaion problems..
aslong as you have a serface to brake down the waves you should be ok..
((You can also get standing waves in the door so adding "Egg crate" to the back wall of you speaker pod if you have room can help .. or acoustic foam)

By the way you plan on paint of cloth on the kicks?
if your doing cloth you can form it across the front and exit that way so you dont cut the car..
Spoze you could do the same with paint but you would add a ton of prep work..

peace troy