Image in background can be override by build list.
Quote text in right shift hudson main right panel column based on its length.
I tried various jelly file and this one fits well to me:

<!--
The MIT License

Copyright (c) 2009 Cliffano Subagio

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<j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form" xmlns:i="jelly:fmt" xmlns:local="local">
<j:set var="img" value="${action.image}"/>

<div style="max-width:400px;">
<img src="${rootURL}/${img.smallIconUrl}" width="48" height="48" />
Foo Bar says: ${action.quote}
<img src="${rootURL}/${img.backgroundImageUrl}" width="100%"/>
</div>

</j:jelly>