The OS valve froze closed (I believe) making the pressure come out the dipstick and valve cover.
Just remove the air box, intake tubes, (inspect and replace lower it cracks at the ribbed area) and the heat shield around the brake booster. It just gives you more room with it out of there. Remove the 13mm bolt and disconnect hoses supported by the dipstick tube. The old O ring will stay in the hole when you pull the tube out. Even though I cleaned the area I still changed the oil just in case dirt got in. If you changed the oil recently no need to do filter.