Two 100lb propane tanks off an RV under mounted behind the rear tires.  To meet my BTU requirements at low temperatures, I needed two tanks to meet the vaporization rates needed.
 
280k BTU wide open
 
Flexible hose from tank valve to 1/2″ black pipe.  1/2″ black pipe to a Fisher Two Stage RS232BBF ($40). 1/2″ black pipe to a tee, one leg 1/2″ to on demand water heater, one leg to service appliances.  3/4″ pipe from 1/2″ once it entered the CAB.  5/8 yellow flex pipe from Home Depot from the 3/4″ black pipe to the appliance regulators.
 
Regulator needs to meet your BTU requirements. The Fisher listed above will flow 350k.
 
No AC.  I wired for it but I’m not sure it will do any good.  I have 3000CFM going through the exhaust hood, that’s like 4 changes a minute of air.  AC will be little more than a little cold air blowing in your face.  I may still add one for non-cooking times.
 
Generator is a 6000w Kipor that actually has died on me.  Working on replacements now but will be a EU3000is Honda and a second one if I add AC. Three year commercial warranty is hard to beat.
 
Started Truck in November.  Worked every Saturday and weeknights until I could not feel my feet any more 🙂
 
Menu is:
Chicken Sandwich
Fish Sandwich
Pork Sandwich
Grilled Mac and Cheese
Italian Melt (Grilled italian cheeses with veggies)
Potato Balls
Ribbon Fries
Apple Fries
 
There are a few more items but you get the idea.  Not all items available at every service.  3 or 4 mains and three sides.
 
If venue will be low volume we go with the grilled sandwiches, mob style events will be faster steam table sandwiches like the chicken and pork.