How to increase width of editable area?

[finestrat]

I tried to increase the width of the editable area using the template html editor from 160px to 166 px because I was getting a horizontal scroll bar on google 160x600 skyscraper ads but it doesn't seem to have worked. The ads are still overlapping the right hand edge of the editable area by a few pixels. Can anybody tell me why it hasn't worked?

<div id="smenu">%LEVEL2MENU%</div>
<div id="earea"><!--%area(area1,166px,)%--></div>
</div>