The header is touchy if you use the logo.gif as you need to change the height for that in includes>languages>youlanguage>header.php

define('HEADER_LOGO_WIDTH', '192px');
define('HEADER_LOGO_HEIGHT', '64px');

You can then make changes to the style sheet for height.

If you have a page not found you should restore your backup copy and try again.

Also any code in the logoWrapper can be removed to ad your custom header if you so choose.