How would you attach these upper cabinets in a high top van?

[magentawave]

When I finally find the van I want I'm going to install a high top on it. If you look at this page here&nbsp;<a href="http://http//sportsmobile.com/1_rb-50ct.html">http://sportsmobile.com/1_rb-50ct.html</a>&nbsp;you will see in the second big photo down the page that they installed some cabinets up high where the bottom of the high top meets the van. I was wondering if anyone knows how those upper cabinets would be installed?&nbsp;<br /><br />Thanks<br />Steve