It was not necessary to remove the red handle or the nut under that. You have to unscrew the next nut down,which removes the valve from the body. Looks like from the picture thats gonna be easier said than done.Good Luck.
OPPSS sorry TG We were posting at the same time,Great minds think alike. LOL
Roger & MaryLou
F350 CREWCAB SW LONG BED
7.3 liter Power Stroke Diesel
1977 27ft OVERLANDER
AIR # 22336 TAC- OH-7
May your roads be straight and smooth and may you always have a tailwind!