1) Remove the two bolts fastening the fuel tank after removing the seat.
2) Push out the red clip of the fuel hose with a flat head screw driver before pulling out the fuel hose from fuel pump.
3) Remove the fuel pump power socket, fuel gauge power socket and also two breather hose at the left side of the fuel tank.
5)You will see 4 Allen screw securing the air box with throttle body, unscrew them and remove the air box(beware to also unplug the engine breather hose connecting air box and engine)
10) Put back the air box as the same sequence and you had done your plug change, do not forget to also wash your air filter seems you already remove your tank. I might be putting a more detail guide on removing the air filter when my BMC filter arrived, time to replace the DNA one haha.