Fuel Gauge Inop

- Could it be a baffle in the tank is installed incorrectly? Need you guys to help me right the ship
If the tank is a replacement that is supposed to be an OEM style there should not be any baffels.

With the sender removed you should be able to see inside to verify.

You mentioned that you were able to put the sender in upside down. Not sure it should be able to do that.

Would you post a part number and a photo of your senders

From what you wrote in the first post you have checked everything I would have done.

The fact that 2 senders are doing the same thing said it is not the sender.

That you can ground the sender wire and the gauge moves / pegs says your guages and ivr are functioning.

Warning: grounding your sender wire for more than a second or two can burn out your guage.

Some things that come to mind is if there is a broken wire in the sender wire that you connect to the sender. It could be that in the natural position the wire is not making connection. In any other position it is making connection.