Okay, this is what I did and it works just fine, so that when an item is on sale the list price will show up. I won't worry about the %off since that does already display on the page.
In skin1/customer/main/product.tpl
Find:
Code:
<tr><td class="ProductPriceConverting" valign="top">{$lng.lbl_price}:</td>
and BEFORE this I put:
Code:
{if $product.list_price gt 0}
<tr>
<td><font class="MarketPrice">{$lng.lbl_market_price}: </font></td>
<td><font class="MarketPrice">{include file="currency.tpl" value=$product.list_price}</font></td>
</tr>
{/if}
I don't use the strikethrough because it makes it hard to read the price.
Hopefully this works okay, and I hope this is helpful for anyone else still searching for this.