So in this topic we gonna show the basic difference in Pre-facelift and Facelift models.
JDM 4th Gen Legacy were released in 2003 and they come on US Market a year later in 2004. Facelift were done in middle of 2006 year in Japan, and in 2007 in USA. So that's why you can eventually see yearly 2006 pre-face and late 2006 facelift JDM Legacies.
USDM: and JDM: Facelift is a minor change in exterior and interior, here's some example of pre-facelift: And some facelift: