Why is gas pouring out of my over flow tube?

I have 2007 Honda Shadow Areo 750cc. I have let it sit for about 1.5 years. I pulled out the choke and when it was trying to start. There was a great deal of fuel pouring out of the over flow tube. I think I have a stuck float. What is the best way to get to it so I can take off the carburetor? Do I need to remove the gas tank and air filter housing?