I pull them out, disassemble, and wire brush. I've never been able to clean much with an air hose or without disassembling. That should keep the rust down for quite a few years. That will also give you access to the tubing and cooling fins for cleaning and rust removal.
On both ours, there are only 2 lag bolts in the rear, small trim screws at the front, 12V wiring, 115V plug, and a gas connection. It weighs less than 100 lbs. so I sit it on a rug and slide it out the door.
You can disassemble the burner without removing the frig from the camper, I just like to sit on a bench where I can get to everything easy. When finish, I can then test it before putting it back in.