[RD] change Banner/Logo with diff css stylesheets

[acdc]

EDIT:
Nevermind, I got it to work

---

This may get complicated. I've been trying this for a few days now with no luck. Maybe you guys can help me. Im using different style sheets with different color schemes and so forth, but i need to be able to change the banner image as well. So far I've got this

.welcomebg img {
css here
}

But...apparently there is no way of changing the image directly. One of my ideas was to remove the banner image all together and place a table with a image and class above the banner to act as the banner. Anyone got any ideas? Any help is appreciated

Oh Yeah, Im using iAlex's welcome table remodel.
<script type="text/javascript">
<!--

/*Welcome Table Customization - By iAlex - Open Source*/
if(pb_username=="Guest"){
     iWelcome='';
}
if(pb_username!="Guest"){
     iWelcome='';
}
document.getElementsByTagName('td').item(5).align='left';
document.getElementsByTagName('font').item(1).style.display='none';
document.getElementsByTagName('td').item(2).style.display='none';
var iVc=document.getElementsByTagName('table').item(0).insertRow(0).insertCell(0);
document.getElementsByTagName('table').item(0).width='1007px';
iVc.className='custbg';
iVc.height='0';
iVc.innerHTML='';

//-->
</script>