If theres enough juice to turn the motor over via the starter, I question whether its voltage issue
because the batttery is in the trunk....
Describe your trunk wiring situation... what size cables and at what point do you have the alt output wire connected to the system ? did you use a union block in the engine compartment or run it all the way back to the trunk too ? Is it grommeted safely ?
Is your battery draining on you if you leave it connected for a few days without running the car ?
couple of other things:
Is the voltage at the coil different from the run positon on the switch compared to the start position, if so, you tell us what youre getting in real life.
Is there a chance you have a bad ignition switch ? (where your key goes)