Best way to edit one page checkout

[dimiandre2]

Good morning,

I need to write a module that edit this file:
/app/design/frontend/base/default/template/checkout/onepage/review/info.phtml

I would like to add a new block under the "agreements" one, but I would like to do that with a module, without editing that file directly

is it possible or the best way is to just edit that file and place inside the module zip ? 

thanks

[qaisar_satti]

add this xml node in your layout xml and change the templates file and make rest the hierarchy child node are  same

<checkout_onepage_review translate="label">
        <label>One Page Checkout Overview</label>
        <!-- Mage_Checkout -->
        <remove name="right"/>
        <remove name="left"/>

        <block type="checkout/onepage_review_info" name="root" output="toHtml" template="checkout/onepage/review/info.phtml">
            <action method="addItemRender"><type>default</type><block>checkout/cart_item_renderer</block><template>checkout/onepage/review/item.phtml</template></action>
            <action method="addItemRender"><type>grouped</type><block>checkout/cart_item_renderer_grouped</block><template>checkout/onepage/review/item.phtml</template></action>
            <action method="addItemRender"><type>configurable</type><block>checkout/cart_item_renderer_configurable</block><template>checkout/onepage/review/item.phtml</template></action>
            <block type="checkout/cart_totals" name="checkout.onepage.review.info.totals" as="totals" template="checkout/onepage/review/totals.phtml"/>
            <block type="core/text_list" name="checkout.onepage.review.info.items.before" as="items_before" translate="label">
                <label>Items Before</label>
            </block>
            <block type="core/text_list" name="checkout.onepage.review.info.items.after" as="items_after" translate="label">
                <label>Items After</label>
            </block>
            <block type="checkout/agreements" name="checkout.onepage.agreements" as="agreements" template="checkout/onepage/agreements.phtml"/>
            <block type="core/template" name="checkout.onepage.review.button" as="button" template="checkout/onepage/review/button.phtml"/>
        </block>
    </checkout_onepage_review>