How do I change or add per piece or yards?

You can add weight to a product so that shipping is added and decide that you don't want to show the weight. You can do that by adding that CSS:
.hikashop_product_weight_main{display: none;}
If, however, you want to display the weight but use piece instead of kg, you can use the advice on that post:
www.hikashop.com/en/support/forum/5-supp...contenance.html#4270
Basically: edit the translations via thte languages tab in the config and add a line KG=piece and that add the file in that post ove the file components/com_hikashop/views/product/tmpl/show.php ( that second step is something which won't be needed after the release of 1.4.2 version )

Concerning the dimension symbols, you can add yards by changing the "dimension symbols" option on the configuration page following our documentation on that:
www.hikashop.com/support/documentation/5...hop-config.html#main

1. That CSS code will hide the display of the weight on the product page. You can edit your CSS in the config under the tab display. But if you want to display the weight on the product page, then you don't need that code.

2. The KG=piece line need to be added in the translation file. For that, you can go in the config under the tab languages and edit it there.