Jennifer,
Yes, you are right:
customer/main/cart_details.tpl
Replace:
Code:
{if $products[prod_num].productcode}{$products[prod_num].productcode}{else}#{$products[prod_num].productid}{/if}. {$products[prod_num].product|truncate:"30":"...":true}
With this:
Code:
{$products[prod_num].product|truncate:"30":"...":true}