Sender trouble

Hi Folks, I have an Series that had a one wire (positive?) Sender unit. I bought the same sender unit as a replacement. But my Truck is negative ground. I've also read one wire senders match only certain gauges. So...is there a way of using my new sender or do I need to convert to a new 2 wire sender and replace gauge? Hope that's not too confusing!

I'm not sure what you're asking. Is your car petrol or diesel? Which series is it? The diesel sender has one wire for the sender and another for the low fuel warning light

Is this fuel gauge?