2005 Silverado Z71 Ext Cab

Hello all.  I have been reading for a few days now and would like to tap into some great minds.  I have a 2005 Silverado and replaced the center console/sub/amp setup for a center jump seat.  I needed to do this to fit two adults and four children.  Anyway I am going to build a sub enclosure for this truck and have purchased two Kicker S10L7 d4 and a Kicker 400.1 mono amp.  I am only going to use one of the subs for this truck.  I don't know what I'll use the other for yet.  Which is the best direction to fire this sub, down or forward?  I can raise the seat about 3/4 inch if necessary to forward fire it.  any other tidbits of info you all can provide will be greatly appreciated.

Under the rear seats or behind the rear seats is an alternative. They sell pre-fab boxes for both areas or you can make your own.Prepare your future. It wasn't the lack of stones that killed the stone age.

Okay let me reword this question. I know there are pre-fab boxes that fire either forward or down for this truck. Whether I buy one of these or build one for myself, which is the better way to fire this sub for the best sound? I could also build a box and fire it up through the rear seat but I'm not sure that would sound very good. I listen to rock more often that not so I'm not into making this truck boom for miles. I prefer the sub to hit hard and low and fast and sound good at the same time.

i must agree down fire si the way to go Suburban boy

Exactly what I wanted to hear.  Okay  I know that a sealed enclosure will give that tight bass but will it extend very low with the limited space I have or should I make it a ported enclosure?  I can make the enclosure to take up both sides under the rear seat but use only one sub and put a por in the other side.  It should give me approximately 1.4 ft^3 for the sub.  I will make the port appropriately sized for the enclosure.  Thanks for the help.  I do appreciate it as I have been out of it for quite some time.

Get a very powerful sub amp with bass boost at about 40-50 Hz, and you can get pretty similar results from a small sealed enclosure.  You won't wake the neighbors, but your low extension should be fine.

What schmiddy said. Prepare your future. It wasn't the lack of stones that killed the stone age.

Okay so firing up through the seat is a no go?