Removing or rotating this fuel tank fitting

[cliffpaul2]

I'm rerouting my fuel line (I'll explain why in a separate thread later) and am wondering if the brass fitting on top of my fuel tank can be removed or rotated about 180 degrees. The fitting is the square one on the right side of the photo below. Thanks in advance for your advice. I don't want to screw something up that will cause me to have to remove the gas tank.