That setup looks nice. A couple of tips:
You'll notice it will take a long time to dry out. You can help that along by filling it with charcoal and lighting it, first time, don't force air through it, just make sure it can draw air on its own and let the fire burn out on its own.
Use only charcoal, not briquettes. The briquettes will leave a lot of clay residue which will instantly smother the fire as soon as they are spent.
You'll always want at least 3 to 4 inches of charcoal burning between the air inlet and your workpiece. Otherwise you are blowing 'cold' air over your piece.
Your setup will work nicely for razor sized objects. If you want to make larger obejcts, you need to have a way to move your piece over the hotspot. This means taking a piece out of the front and back where you can slide your object through.