I apologize that I have not had time to add much detail to the steps but there are some rough designs that I worked off of that are on linked on the next step. If you have questions please post them and I'll try to respond or add the the instructable.
Step 1: Design
1. The bar top is too close to the bottom "work area" and 2. The work area does not extend back very far leaving little work space. So I shifted the top forward leaving some of the 2x4's exposed. This was not to be desired but still works well.