Gas Tank Switch in 76 Chevy

I'm not sure if this is the right forum for this, but whatever.

I'm trying to move the gas tank in my 1/2 ton Chevy from the factory sidesaddle location. I've heard that it's possible to use a tank out of a full-size Blazer between the framerails behind the axle as a replacement. Has anyone done this? Anything I need to be aware of before attempting it?

Any help appreciated.

-Jon