Issue: Inconsistent voltage - Since relocating the battery to the trunk, I've noticed inconsistent voltage at various times and at various points on the car. 

Solution: Although I'm 98% certain the variations I've noticed are due to poor grounding, I will go the extra mile or so and thoroughly redesign the power distribution units under both the dash and the hood, as well as upgrade the alternator output wire to a larger gauge.  I'll also implement one of those "central earth" grounding systems to ensure I have a consistent ground throughout the car.

Over the weekend of August 10th, I started digging into all the wiring that had been added to the car to accommodate the various gauges, controllers, alarm, and stereo gear, that have been added over time.  And, the more I dug, the more I didn't like what I was seeing.. a bunch of spaghetti.  Now, I am pretty good at wiring, and have not had any shorts, blown fuses, or other problems (other than insufficient grounds) yet, I decided to redo everything.  So, I gutted all the non-factory wiring and am in the process of redoing everything.  So, with the front bumper cover off, the fender liners out, along with the seats (F & R), center console and center console of the dash... it's looking pretty barren.. I've also removed all the wiring for the fuse-box which I relo'd to the hatch with the battery; and, the fuse-box will make a return trip back to under the hood near its original location. Over the past few weeks, I've scoured JC Whitney, Home Depot, a couple stereo shops, and a couple electronic parts outlets here in Houston for all the components I need to rebuilt the power and ground systems the we they need to be done.

Outcome: SUCCESS!!   I started the engine with the new wiring in place on Sunday, Sept 14, and found I had 14.5v pretty-much all the time with the engine running and the headlights on.

Key Accomplishments:

• added two independent and individually adjustable switches to the clutch pedal - one switch each for flat-shift and launch control.
• rewired the fuel pump with 12 ga. wire, adding a relay in the rear hatch such that the Autronic SMC trips the relay which then applies +12v power to the fuel pump directly from the battery
• new power distribution unit (PDU) - This has been fabricated and close to permanent installation.
• mounted Greddy gauge controllers in center console. 
• mounted the Autometer ProComp warning lights on the lower gauge pod on the A-pillar
• fabricated mounts in the front left corner of the engine compartment for a series of relays.  Although I'm planning to use only four relays at present (two for fans, one each for nitrous and IC spray), the mount will support up to eight relays.  And, for those who wonder, the zip-ties are temporary; I'll permanently pop-rivet the relays to the mount when I'm through fabricating and wiring them into their respective circuits.
• fabricated a new mount for the fuse-box so I can relocated it from the hatch to the front-left corner of the engine compartment.
• fabricated an intermediate harness which connects the Autronic SMC to the new primary control box.
• relocated the factory fuse-box to the front-left corner of the engine compartment.
• fabricated a central ground system for under the hood.. connected up the twin coil pack, both igniters, throttle-body and both factory under-hood ground points. All are connected via 8 ga. stereo power cable to a 3" x 1" strip of copper that is mounted on a steel brace just off the alternator mount.  This copper strip has a 2 ga wire running to a second center ground point located under the rear seat, which is a connect point for various 8 ga ground cables from the stereo amps and a couple factory ground points under the dash.  This 2nd ground point is then connected to the (-) side of the battery with another section of 2 ga. cable.
• fabricated a nice bracket for a small switch that will make contact at 95-100% throttle.  NOTE: I was going to use this as part of the nitrous activation system but have since learned that I can allow the Autronic SMC utilize throttle position in its control of nitrous activation.  So, I no longer need to this switch...Fun fun!
• rewired alternator output with 2 ga. wire that runs across the front of the car, under the ac condenser, to the 1 ga cable that connects to the starter.  This will ensure a good path of current flow to the battery.
• rewired alternator inputs
• rewired a/c compressor circuit
• rewired pre- and post-IC temp senders
• fabricated a single harness to the stock factory fan temp switch (located in the bottom tank), the n/b O2 sensor, and the MR2T oil level switch
• ran additional wires to an adjustable pressure switch that will be used in conjunction with the Autronic SMC to control nitrous activation.  This pressure sender will trigger nitrous below a certain level of boost, at which point nitrous flow will terminate.
• rewired existing oil pressure, oil temp, engine temp, and trans temp gauges, and installed new wiring for oil pressure and engine temp warnings
• I've made several modifications to both the engine wiring harness and the Autronic SMC wiring pigtail.  Wires that are no longer needed were removed while other necessary wires were added.