Increase Comment Box Width

For about half year ago, Blogger.com have updated the comment style into comment-form as an option for the old one. While in 2009, many converter transform magazine style into XML Templates. So, the comment box style is a need because it use a wide view of comment box. However, blogger have set the width of the box only about 300px and that is short. Now, come question, is it possible the increase the box width of comment? Quickly I answered, yes it is possible. But, How to do it??
This article explain about how to increase the width of comment box easily...

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1. Go to LAYOUT -- Edit HTML -- (checked expand widget template)
Find this tag :

<iframe allowtransparency='true' expr:src='data:post.commentFormIframeSrc' frameborder='0' height='275' id='comment-editor' scrolling='auto' width='100%'/>

2. Please see the tag width='100%'

3. After that, change 100% with your own size. But, before you make changing, you have to consider about your main post wrapper. For example: if your mainpost-wrapper is 500px then the comment box width is less, i.e. 490px, 480px or etc.

4. Save your Template.

So it's easy... right guys... :)