You will need to unscrew the sides of the unit which houses the dials and ignition (This is connected to the burners). Pull it out, and they should come off rather easy if they are old. Slide them towards the front and out of the rear slots. When putting the new ones in, it is as simple as reversing what you did to take them out. You will need to go forward, into the holes, then toward the rear slots and lock them in place. You will then line up everything and screw the unit back into place. Much easier if you can get someone to help you for 10 minutes, but easily done by 1.

There is a keeper ring ( looks like a bobby pin / hair pin ), that holds the burner tube to the gas valve, remove it and the tube slides off.

I have a Ducane 5 burner, solution 2 is exatly right, thanks.