Copy this folder to your PC. Double-click the itssecured1a.htm file to open it in your browser. It demonstrates how to arrange the HTML and CSS so the columns are as you described.
Most of the changes to the CSS are at the bottom. Not all, but most.
The HTML below the .rotator is boxed differently. #col and #col2 are replace by #colLeft and #colRight.
I left several outlines in place so you can visualize how the boxes are arranged. Comment-out or delete the outlines when you're finished with them.
Please let me know after you have downloaded the file.