It appears that your az_logo is 208 pixels in height and that is the reason you see what you do.
IF your picture is NOT 208 pixels in height, you need to change the setting in your header.php.
If it is 208 pixels in height, you can change it by cropping off the bottom white space. You will still need to make sure the setting in the header.php so that it is not larger than the logo.gif
Adding an additional graphic can be done in several ways. Simplest is to combine them into one az_logo.gif.
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