See Urban Frederickson's color cross reference sharts at IPMS Stockholm
http://ipmsstockholm.org/colorcharts/stuff_eng_colorcharts_gunze.htm
For what its worth, neither the Gunze nor the Tamiya will get you 'accurate' colors. For that, the paint of choice is White Ensign's Colurcoat line in enamels and the MM Acryl II Marine line of paints (now discontinued, but still available) in acrylics. PollyScale gets you close, but not totally accurate