Hello Yendor!
I add in my Path a 12 V plug and a power outputs in the back of the center console.
Both are wired with independient fuses direct from the battery, I use Diam 8 mm cable ( near to AWG 1 ) the wires enter near to the main hardness cables an pass below the mat floor insulated by independient plastic tubes protection.
The 12 V plug is used for accesories ( batteries charger, ligths, PC, etc ) and the power output to conecting the 12V / 220V converter , auxiliar and battery charger and others.
Is easy follow the power cable to the cargo area below the mat floor in order to install more outputs there.
I hope this helps.
Un abrazo
JAD