It took about a month for me to build the amps into my back seat but the work was well worth it.  This page will give you detailed step-by-step instructions on how to do this on your own or just to get you familiar with the internals of your back seat.

• Supplies cost me roughly $144.81 but would have been $120 if I didn't screw up the plexiglass TWICE
• Hours to complete: 45
• Trip to home depot: 9
• Supplied necessary to complete: ¹/₄" staples, gray carpeting, plywood, spare MDF, electrical fasteners, ¹/₄" plexiglass, 1 ⁵/₈" drywall screws, 1-¹/₂"x18"x18" foam padding
• Amps: $560
• Wiring: $60

	This is what the internals of the back seat look like when the cover is stripped away.  That cover simply unzips on the bottom and you will have to pry each of the c-clips holding its form.  These won't be reused.
	The padding isn't attached by any special means and this is what gives the seat rigidity.
	I made a rough cutout with a Roto-zip to the outer dimensions of my amps as they would be sitting in the seat.
	I chose wood (any 5-ply plywood is fine really) to mount the amps to.  It doesn't conduct electricity - so I won't get a ground loop - and its quite rigid. I built the sides to rest on the flat parts of the plastic panel.
	This is a rough fitting to see how the amps would sit on the wood.  I took a marker and lightly outlined their shape and screw holes as well as the holes for the wiring before taking them off.
	This is the side that people will sit against.  I bought two pads of high density foam used to reupholster dining room chairs measuring 2" thick by about 18" on each side and stapled the corners to the wood to keep them centered as the fabric was pulled over the seat again. All wiring was run on this side and stapled to the wood.  The difference in comfort is almost negligible.
	Final fit with the plastic screwed onto the plywood and amps mounted to plywood.  I bought two computer case cooling fans from Best Buy and ran them to a relay mounted to the wood.  This relay is powered off the main positive wire (always live) from the subwoofer amp and turns the whole system on.
	Test fitting the plexiglass after the fabric was stretched back over the seat.  I simply cut the fabric as best I could about 2 inches smaller than the opening in order to fold it down the sides.
	A side shot, showing the fans and plexiglass installed.  I used screws with a hex drive on the plexi in order to act as a small theft deterrent (of course the glass can be broken, but not easily as it rests against the amps).
	The final product installed in the car.  All wiring was permanently stapled into the seat and run down the sides to the corners where it exits the fabric.  I coiled everything up to make the installation as easy as possible.
	Shot of the seat as it sits upright.  Placement of the fans at the top is necessary as in this position they are still exposed to cool the compartment.
	I installed an ELstringlight along the bottom of the rack to give a cool effect at night.  This was run as a separate power wire to a switch on the console.  It works but has a side effect of inducing noise into the signal when it is on - not a very loud noise, but noticeable.
	Another shot of the seat folded down.  Here you can see the wood bracing I installed along the top for support of the plexiglass.  The middle support is wide and acts as a wall to force air over the amps instead of bypassing them and flowing along the top.
	In 1990, thirdgens were equipped with shoulder belts, eliminating the lap belt location and enabling me to install my distribution block in that location.
	Another shot of the distribution block.