I have the following on my truck.
tool compartment under the driver
full set of combination wrenches up to 1 1/8" and another 5 wrench set for larger stuff
3 socket sets, 1/8, 1/4 and 1/2" and sockets for 3/4 and 1" in some sizes plus bars and extensions for those
hex socket set
other tools, sprays and some odd specific tools of the air compressor plus spare belts.
Spare head lights
Tire iron and bar
Under the bed in a storage slot/bracket 48" black pipe breaker bar.
In the cab under the seats
20lb fire extinguisher
Road Flares
Road Triangle set
ECWCS jacket
coveralls (tanker suit)
Yellow rain suit
Full set of screwdrivers
Full set of pliers needle and channel locks
ball peen hammer, drifts and punches
larger sledge
wire tools, wire, tape and ends
two flashlights
Digital Multi Meter
cotter pins and winch shear pins
In the glove box
Spare bulb box from a tank with all the bulbs duplicated save the headlights
In a 5 ton tool box bolted to the bed
Air tool set with 1/2" Impact, grider and impact hammer
Pioneer tools
Vice grips
Tire changing tools will go on as well (for breaking down rims/wheels) as well as a spare flap and tube
6 sets of chain binders and 6 sets of grade 70 5/16" chain
2 20 foot sections of 3/8" grade 43 chain with slip hooks
2 sets of grade 70 3/8" chain
x3 5 Ton Snatch Blocks
20 ton bottle jack
longer 1" breaker bar and ratchet handle
Big set of 1" sized sockets
Prybar
30" tire spoon
Air hose and gladhand
x2 coiled air lines
In the bed
Spare oil
Spare Antifreeze
x2 jerry cans empty
x2 6 ton jackstands