difference between subaru td04's?

[Ben]

Thanks for the info, very useful. Now for my next question, is it just the 2000-2004 impreza which has the td04l-13t? Because I have found quite a few turbo's from imprezas aged between 93 and 99 which have turbos which say td04l on the name plate, but do not give the '13t' or '13g' '15g' etc..