Starting some Builds not too extreme but goood...

Next week we got a Line Up of my Co-workers vehicles that are going to get systems.... First we have a 2006 Nissan 350z Convertible that is going to get polk comps up front and kicker cvt 6.5 subs in the rear speaker place using the trunk as the box anyone have any input on it? we will be using a Cadence 4 channel for that.
Then we have a 2002 Corolla that is getting an Alpine 9884, polk comps front and rear and a kicker 15 cvr off a china brand amp cause he is getting the whole set up for only 400 bucks.
1997 Chevy chayenne... Got a Kenwood x994 with infinity kappa comps up front and we are trying to decide on a sub setup for his truck which is between a pioneer bi-flat sub and maybe 2 8in bazooka tubes....
any suggestions would be greatly appreciated ill post pics as the vehicles get done up...