Ford Sierra & Scorpio Head Gasket. FORD Scorpio Mk1 Hatchback (GAE, GGE) (Year of Construction 05.1985 - 10.1994). FORD Sierra Mk2 Hatchback (GBC, GBG) (Year of Construction 01.1987 - 03.1993). FORD Sierra Mk2 Saloon (GBC, GB4) (Year of Construction 01.1987 - 03.1993).