Welcome
If its got pink injectors i'm guessing it probably had a vf35 on it as its the most usual swap. If its been mapped for that and the last owner just swapped the turbo back before selling then i'd definitely get the map sorted now, especially as you know fuel mix/boost aren't right. Where did it go on a dyno? Even on a td04 with a full decat you should be somewhere around 280 rather than the 250 you're seeing once the map is fixed.
