Can I install a new fuel sender unit on a 72 duster without removing the tank?

I filled up my (new to me) duster tonight and the tank started leaking like crazy wile I was still at the pump. I drove the car home and parked it in my gargae and now it's barely leaking but obviously I need to fix this. The gas gauge doesn't read "full" so that leads me to suspect the sending unit has failed and/or the gasket is leaking.

I could take my car to my local speed shop (who does great work but pricey) to have the job done. However, if this is something I can tackle myself I'd like to try. I know I have to get most of the gas out of the tank so I guess I'll be cruising around this weekend to burn some of it off (hey!! not a bad way to spend a weekeind right?!)

So if anyone can point me in the right direction I'd appreciate it!