Fuel Gauge Not Working!

Hello, I recently bought a fuel gauge and sending unit and installed them in my 67 bug at the same time but I still can't get any kind of reading off it. Sadly I forgot which way the wires connect to the gauge. So I tried both ways (Did I fry the gauge by chance?) My fuses are all good and my connections are fine. If anyone could tell me how to test the sending unit and gauge or if you have another idea I would appreciate it very much. Thank you!

Was the gauge marked with a + & - or numbers like a 15 & 1? If you ground the wire from the sender to the gauge with the key on it should read full tank.

Well there is a G on the driver's side of the gauge right above the wire terminal. That's all I see except for the part number. And I tested the gauge with an ohm meter and it had continuity. Do you think it could still be bad if it has continuity through it?