CSS Position Overlapping Image

I am struggling to get this page to display correctly in IE7: http://www.towkars.org/dmv-new.php

The page displays fine in Google Chrome and FireFox, but in IE7 the "Road Sign" image is partially cut off.  I want the full image to display, and to extend down the right side, without causing any text wrapping (from float), just as it does in FireFox / Chrome.  Essentially I just want to statically position the image at a certain pixel coordinate (relative to the other images on the page), and have the image  be on top of anything else.  I also did not have any luck using the z-index, as it does not seem to make any difference.

Thank you in advance!

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    </div><h1>Utah DMV Forms to Donate Your Car</h1>

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