What we did was this.....
table[class="tbl"] .hide-for-small {
display: none !important;
font-size: 0 !important;
line-height: 0 !important;
height: 0 !important;
width: 0 !important;
margin: 0 !important;
padding: 0 !important;
}
table[class="body"] .show-for-desktop {
display: none !important;
}
table[class="body"] .show-for-small {
display: inherit !important;
height: auto !important;
line-height: 0 !important;
}
td[class="mobile-hide"], td[class="mobile-hide"] img {
display: none !important;
font-size: 0 !important;
line-height: 0 !important;
height: 0 !important;
width: 0 !important;
margin: 0 !important;
padding: 0 !important;
}
img[id="mobile-fill"] {
display:block !important;
width: 100% !important;
height: auto !important;
}
div[id="hidden-image"] {
display: block !important;
width:100% !important;
height: auto !important;
}
table[class="tbl"] .hide-for-desktop {
display: inherit !important;
}
<div id="hidden-image" style="display: none; font-size: 0; height: 0; line-height: 0; margin:0; padding: 0; mso-hide: all;overflow:hidden;">
<a href="LINK" target="_blank" style="color: #2ba6cb; text-decoration: none;">
<img src="IMAGE_URL" style="border: none;" id="mobile-fill" width="0" height="0" border="0" />
</a>
</div>