My Autometer fuel gage reads backwards

[chevelleven]

Hi, I have a new Autometer 2 1/16 Street Rod Artic White fuel gage installed in my 71 Chevelle. I kept the original tank sender unit. I connected "S" to sender (Tan wire), "I" to + from ignition and "GND" to ground. Now the fact is that when the tank is full, the pointer reads a little bit over "1/2", and while the fuel is being consumed and the tank level goes lower, the pointer moves gradually toward "F" until it reaches the gage top and can´t keep moving further (So, it is reading backwards).

I´ve checked the wiring, connections, grounding, etc., and still can´t fix the problem.

Can the tank sender unit and floater be installed backwards? When I installed the mine, I think it had only one possible position to be attached.

The original gage (Non SS) reads "F" at top and "E" at bottom, so the pointer travels clockwise from F to E. The Autometer gage pointer travels from right F to left E (Counterclockwise), Could this be the problem?

Thanks for the help!