SB-GM-TRKDBL/10WØ Stealthbox™
Fits 1988 - 1998 Extended-Cab
Full-Size GM Pickup Trucks
Installation Guide:
This Stealthbox is a product which requires professional installation skills and tools. Please read this
installation guide thoroughly before beginning the project. It will guide you step by step through the
installation. Several of the steps in this process may require two people to accomplish.
It is absolutely vital that the enclosure be properly mounted to the vehicle according to these instructions. Failure to mount the enclosure properly presents two problems: 1) the sub-bass performance
will suffer due to the movement of the enclosure caused by the force exerted by the woofer and 2) A
loose enclosure presents a serious safety hazard in the event of a collision or sudden deceleration.
STEP 1: Fold the rear bench seat up.
STEP 2: Permanently remove the under-seat tool box. All
holes used for mounting the tool kit should be sealed with
rubber plugs or silicone (not included). The mounting area
must not have any protrusions rising up from the floor.
STEP 3: Run speaker wires to the rear of the cab under the
bench seat.
STEP 4: Peel the backing from the two supplied squares of
wax and place them on the floor of the cab. One wax square
should cover the factory tool kit mounting hole as shown at
right, the other should be located in the area of the mounting
bolt on the driver side of the Stealthbox.
STEP 5: Thread the two supplied bolts into the threaded inserts in the Stealthbox. Tighten Fully.
SB-GM-TRKDBL/10WØ, JL AUDIO, Inc 1999 • Page 1
Sheet SKU#011123 Revision 8/8/00
STEP 6: Place the Stealthbox in its mounting location on the floor of the cab. Press down on the
enclosure firmly to make an impression on the wax sheets with the heads of the mounting bolts.
STEP 7: Remove the enclosure. There should be clear marks where the bolts pressed into the wax
square.
CAUTION: The mounting hole is near the exhaust system of the vehicle. Make sure that it has had
time to cool before proceeding with the following steps.
STEP 8: Check under the truck for any loose brake lines, fuel lines or other hazards before drilling.
STEP 9: Drill a 1/2" diameter hole through the floor pan of
the truck using the indentation in each wax square as a guide.
Always wear eye protection when drilling.
NOTE: On some third door models there is a heat shield
under the passenger floor of the truck. A hole should be
drilled through the heat shield large enough for the fender
washer to pass through.
STEP 10: Trim speaker wire to length and connect to the enclosure's barrier strip observing correct
polarity. Positive is designated by the red wire on the barrier strip.
STEP 11: Place the Stealthbox into its mounting location, tucking the excess wire neatly out of sight.
Turn on the system and test the enclosure's operation before bolting it down.
STEP 12: While one person holds the Stealthbox in place inside the truck, bolt the enclosure into place
from underneath the truck using the supplied hardware. Before tightening the bolts, apply a bead of
silicone sealant between each flat washer and the vehicle's floor pan. Tighten the enclosure fully. See
diagram below:
Enclosure Wall (fiberglass)
Flat Washer
Split Lock Washer
3/8" Bolt
Threaded Insert
Molded into
Enclosure
Car's Sheet Metal
Bead of Silicone Sealant
SB-GM-TRKDBL/10WØ, JL AUDIO, Inc 1999 • Page 2
Sheet SKU#011123 Revision 8/8/00