It bolts on with the bolt heads in the engine compartment. you might need to move some stuff to get to them though, and be careful as they often shear when trying to undo them, the pull out the filler neck, and remove the plastic splash guard to get the tank out...(TBH the wing is normally off when I do this, but it should come out with the wing on I reckon..)
Personally I would not remove it...shove a hose pipe down the filler neck and turn it flat out so it flushes it, then drain it (disconnect the washer jet pipe up by the bulkhead somewhere), they pump out real quick then...(redneck pressure washer for clearing a mud siezed clutch using a bit of extra pipe at one of the fog annual meets!)....Once empty, tip some bleach in it and then fill again with water and leave to fester...then drain again, fill and drain to flush, and the refill and connect the pipe to the washer jets.
Honestly this will be quicker, and you wont risk breaking the bottle trying to undo it...and you dont have to crawl around on the floor inside the wheel arch...Can all be done standing, and plenty of places to rest a beer as you do it!