Yes the factory fuel gauge works with the Yosh tank. I'm not sure if it will remain on full till the extra capacity is used or if the fuel sending unit will include the increased capacity.
Either way I always use the trip meter reset every time I fill up to get a more accurate remaining mileage estimate when the fuel gauge reads near empty.
cheers
ken
I would think that it may not register the 'extra' fuel accurately but once level comes down a bit register accurately to empty ?