Did you clean your ground point down to metal ? Are you using 1/0 for the big three ? When was the last time your battery was topped off (is it brand new or used)?
why ot use that angled space behind the seat to increase the enclosure size, that way you can build the port like mentioned above and not have to extend it outside of the box (perhaps).
When you say connecting - do you mean its just plugged in or powered on playing music ?
Also, did you mention earlier that you are grounded to the floorpan?? if yes relocate to a quality ground - do you have a picture of your Big 3 ground location ?
Question about the Skar amps (1500.1D specifically) -
Working Voltage : 8.5V-16V
Will using this amp with 14v batteries charging in the mid 16.x volts range void the warranty ?
***Please no one call me boy***
Honestly 35k seems low. Even for starting pay. I would aim a bit higher - nothing rediculous but...somthing more respectible since you will be THE IT guy. Consider people make more in a mindless factor production position (with OT).
when you say "full tilt" do you mean the volume turned all the way up or set to dd1 max?
regardless, dd1 will tell you how to set your gains. it does not compensate for subs in the wrong enclosure
add possibly this