I have a 1994 150hp mercury XR6 that came with the trim sender already installed. I installed trim gauge designed for mercury engines and it is reading in reverse. I tested the gauge to make sure it was working properly by disconnecting the sender wire and the needle went to full trim and then grounded the sender post and it went to full down. I then tested the ohms coming from the sender. When I trim up, the ohms decrease and when I trim down the ohms increase. My understanding is that this is working in reverse. According to documentation that I have read from 3 different trim gauge manufacturers, the ohms from the sender should be 10 ohms when the motor is down and 160 ohms when it is up so the ohms should decrease when the motor is lowered and increase when it is raised.

Do I need a different sender or is there something else that I am not seeing?