For smoke I use the A-MAZE-N 5X8 pellet tray and for racks stainless steel was just to expensive so I used aluminum expanded metal.
Here is a list of electronics I used for temp control-
Thermometers for the door – wanted something low enough to show 90°, purchased Cooper thermometer 2” dial with 5” stem our range was -40° to 180°. We bought these locally from a restaurant supply company in town.
http://www.us.sbt.siemens.com/sbttemplates/library/pdf/155019.pdf user manual from the part
http://www.energyequipment.com/c-48-thermostats.aspx - this is the site we bought ours from but I don’t see our model # there anymore. Maybe call and see what would be a replacement.
Product # - 141-0521
Please be safe and know what your doing, your playing with propane which is explosive and wouldn't want to hear of any accidents.