The tank capacity was increased, that was the whole idea behind the tunnel being lowered.Looks like a lot of repair to me... lol.
So, when you lowered the tunnel, that obviously increased the capacity, but did you weld the mounting tabs back in the same location so the tank is in the same height relative to the bike? IOW, did you just remove some of the wasted space between the tank tunnel and the bike frame? Or does it in fact ride higher?
When the 250 tank is installed on the 450 there is a large space between the tunnel and the frame, I simply used that wasted space and welded the tabs back in the same place so the tank is at the same height.