Hello curly joe and welcome to the forum.
I'll echo what Toker and Habanero said, never need to clean the interior of your smoker. I just wash my V-tray and racks after each smoke as well as wipe off any grease and/or moisture from the interior with a paper towel. I use rubbing alcohol on a paper towel and wipe down the door seal and where the seal contacts the smoke box to remove any grease, dirt and moisture. That's it. When the black "seasoning" on the interior starts to flake and peel I crumple some aluminum foil, or a use a BBQ brush, and rub the box interior to remove any flakes. After smoking and cleaning I leave the door open to dry out the smoker till next time.