Hi,
So you have to set the option "Show taxed prices" to "No tax". But this will remove the taxed prices in the whole shop.
If you want the prices with tax and this kind of layout for the cart / invoice, etc.
You can edit the corresponding views and use code like:
$origValue = $this->params->get('price_with_tax');
$this->params->set('price_with_tax','0');
At the top of the view "checkout / cart" for the cart in the checkout, or "order / show" in frontend template or "order / invoice" in backend template for the invoice.
And this code at the end:
$this->params->set('price_with_tax',$origValue);