[ron skeen]

Paul,
I haven't replaced mine, but have seen it done.  The sending unit is an aluminum tube that is about 2 1/2" round.  The fuel tank has to be slid out partially as the unit comes out the top, straight up.

The black knob is a pump to reprime the engine if it runs out of fuel.

I have replaced the fuel sending unit in 96 and 04. You do not have to move the fuel tank. They are at least 2 different lengths tubes.