Hi. I am looking at option two in my case. Firstly I have 4g wire from front of car to distro block in the trunk with carputer. Then from distro block, two 8g wires to power amp and Opus (I am only using 8g instead of something cheaper because I already bought it to run from battery but then bought amp so 8 wasn't going to cut it.) The IGN wire in this case is using a good section of speaker wire (split in half) using the copper wire to run from origainal HU's wiring harness (bought an aerpro plug for my car).

Is this ok so far? How do I split the IGN wire to power both Opus and Amp (bit of a noobie to circuitry)