My 1993 Previa needs either an Intake gasket or Head gasket. Is there an easy way to determine which? No oil in radiator, no water in crankcase. Large cloud of white smoke at exhaust, smell like antifreeze. Considering attempting repairs myself. Have the Previa Shop Manual, don't see if the Head can come off (via the opening under passenger seat) without dropping the engine? I would assume No? Thanks. Choz.