I have dual tanks in which both tanks have mechanical fuel sensors. I've removed one tank, drained it and tested the sensor, all ok except the wires to the sensor were snipped off by who knows who? 
The other tank is still fiber-glassed in but I don't really want to remove it as it is ok as far as fuel delivery goes. This tank had a problem delivering fuel and I am guessing the plastic pickup tube expanded and was pressed against the bottom not allowing a good flow. Does that sounds possible?
I think I may switch to a copper pick up tube, at least in this tank.
I only have one fuel gauge so where do I connect the snipped wires to? Do I run them to the gauge like the other ones and if so, how do I know which tank the guage is reading?? I'm a bit confused.  

Yes, one fuel line from each tank goes to a T connector then to the fuel pump. But why does each tank have a fuel sensor?
Also, how or where do I connect the one that has been cut? Seems odd that someone just cut the line when it must have been hooked up to something.

i just had a feeling that GT was going to help he is VERY KNOWLEDGEABLE and good luck rusty

I have 2 tanks, 2 senders, 2 guages.