tunability

Hi all, does anyone have the relevant information to unpin the harness to make it stand alone struggling to find accurate information on how to do this for the Australian harness

I’ve heard it’s best to buy from other aftermarket places than eBay they say a lot of companies there scam and What’s the best tuning chip to use and is turbo charging the car worth it? Seen a lot of videos in Aus where the hit above 800Hp also what exhaust is worth buying and That’s about it...