Tach ????????

I have a 2002 F225 Yahama 4 stroke and am trying to install a digital tack
but something doesn't seem right. Here's what I have.
tach 6Y5-8350T-82-BK
lead 68F-82553-90-00
read 6Y5-83553-N0-00
cover 6R8-82582-00
control 703
I don't see where the wires plug in the motor at.
Dealer said this is what I needed.
Help would be very welcome

[boats.net]

There will 2 square off white colored connectors next to the main 10 pin harness that your 68F harness connects to.

I have one off white conection pluged in to each other do I unplug it and plug into each end ?

[boats.net]

The square 4 prong off white colored conectors on engine should not be plugged each other, the male connects to female connector on harness going to gauges and female engine to male gauge harness.

Thanks very much. I bought the engine new and its always been like that do you think that has caused any damage to the engine.