I'll add my 2 cents here. I have an AEM wideband AF gauge, and the Nexus Boost/Vac, Fuel Pressure and Water Temp.
I also have a few other goodies on the car if you need any more ideas on where you can spend a ton of money:
ENGINE
Kenne Bell 2.4L Supercharger
Kenne Bell 8-Rib Pulley Set-up with 3” Upper Pulley, 12psi
Ford Teksid Aluminum Block, bored 0.020" over
Ford Cobra 8-Bolt Forged Crank
Scat 4340 H-Beam Forged Rods, w/ARP 2000 Bolts
JE Custom Forged Coated Pistons
ARP Head Studs
Autolite HT0 Spark Plugs
Moroso Aluminum 7-Qt Oil Pan
Ford Triton V-10 Flexplate
Meziere Electric Water Pump
DiabloSport MAFia
Powdercoated Cam Covers
Optima Yellow Top Battery
Engine Built/Tuned by S.T. Motorsports, San Bernardino
Machine Work-Dougan’s Race Machine HEADS
Livernois Stage 2 Ported & Polished
Livernois Performance Valve Springs
Manley Inconel Valves, +1mm
TRANSMISSION
5R55S Street/Strip Rebuild, with 3000rpm Torque Converter
FUEL SYSTEM
39# Fuel Injectors
Kenne Bell Boost-a-Pump
EXHAUST
Dynatech SS Long Tube Headers, 1-3/4” w/Jet-Hot Coating
Dynatech X-Pipe
Exhaust Cutouts, with Electric Valves
Magnaflow Axle-Back Mufflers
REAR END
FRPP 4.10 Gears, 8.8”
Detroit TrueTrac Differential
Powerhouse Aluminum Driveshaft
BMR Driveshaft Loop
Moser 31-spline Axles, 3” Studs
Moser Rear End Girdle
SUSPENSION
BMR Tubular K-member
BMR Radiator Support/Sway Bar Delete
BMR Adjustable Lower Control Arms
BMR Adjustable Panhard Rod
BMR Panhard Relocation Bracket
BMR Adjustable Upper Control Arm
Spohn Rear UCA Housing Bushing Kit
Strange Adjustable Rear Shocks
BRAKES
Dual Line Lock Solenoids
PowerSlot Front Rotors
Hawk HPS Brake Pads, Front & Rear
TIRES/WHEELS
Street:
17 x 9 Chrome Bullitt Wheels
Nitto 450 255/50-17, Front
Nitto 450 275/50-17, Rear
Track:
Weld Draglite XP, 15x9, 5.5bs
Mickey Thompson ET Drag slicks, 28x10.50-15
Weld Draglite, 15x3.5 - 1.75bs
Mickey Thompson ET Front Tires, 26x4.50-15
EXTERIOR
CDC Shaker Scoop (modified)
CDC Classic Chin Spoiler
Chase Taillights
Clear Corner Lenses and Stealth Bulbs
Window Tint, 5%
Redline Hood Struts
INTERIOR
Autometer Nexus Controller Module
Autometer Nexus Boost/Vac Gauge
Autometer Nexus Water Temp Gauge
Autometer Nexus Fuel Pressure Gauge
AEM Wideband Air/Fuel Ratio Gauge
SOS 2-Gauge Pillar Pod
Custom Center Vent Panel Gauge Pod
Fan, Line Lock & Cutout Switches
Dash Kit