Need to display discounted price when using price groups

[gjt]

I am using Miva's price groups to create a storewide discount on all products for an upcoming sale. The price group I've set up works fine and as expected.

However, I want the discounted price to be displayed on PROD. i.e. I want the regular price to use a strikethrough as well as displaying the discounted sale price. Pricing is displayed like this...

<mvt:if expr="l.settings:product:base_price GT l.settings:product:price">
     <s id="js-additional-price" class="product-additional-price">&mvt:product:formatted_base_price;</s>
</mvt:if>

<span id="js-price-value" class="product-price" data-base-price="&mvt:product:price;">
    <mvt:if expr="l.settings:product:price NE '0.00'">&mvt:product:formatted_price;</mvt:if>
</span>

Currently, the regular price displays even though the actual price is discounted (which you can see when on BASK). Also, FWIW, there is a message beneath the regular price that reads "10% Thanksgiving Discount: $7.99" which is displayed using the following code...

<div id="js-product-discounts"></div>

I've been able to do this in the past using custom product fields and Toolkit but that's not an option in this particular case (I don't think). How can you do get the regular price to use strikethrough plus display the discounted price when price group functionality is setting the actual selling price?

FYI, the Readytheme being used is Levels.