Changing normal rate to tax amount

-- HikaShop version -- : 2.2.2
-- Joomla version -- : 2.5.16
-- PHP version -- : 5.4.7
-- Browser(s) name and version -- : IE 10

HI there. Trying to work out how to change the wording Normal Rate that shows during the check out and on an order when viewed.
Would prefer it to show Tax(gst).
I looked through the language file to try do an override but could not find this.
Any help appreciated.

That is the tax namekey that you entered in your tax rate via the "manage tax rates" button of the System>Taxes menu. It's not a translation. Simply create another tax rate with the tax namekey that you want and select it in your tax rules and that's it.