just done that, bit fiddly but easy, first remove wind deflector by unloosening the two screws to the right no need to take them out next remove the screw to left underneath and slide the wind shield to left and remove. You should now see the burner assembly, one screw hold it place remove said screw and will drop down for you to blow clear, use a compressed air can and blow through the gas body has well. reverse the procedure to reinstate.
p.s. the wind deflector is the awkward bit I used a flexible screw driver, good luck.