1998 yamaha 250 ox66

I am taking of two 1998 yamaha 250 ox66 and putting on two 2005 yamaha 300 hpdi will i be able to use all of the same gauges and ignition harneses? Is there anything i need to replace?

I also need to put a new seastar hydrolic stearing system on this boat any sugestions?

[boats.net]

The gauges will work but the 2005 wiring is different, the 2005 gauge harness on engine only uses 1 square connector(you wont use the other connector on your harness) so you will need to install an adapter harness(part number 6Y5-85335-00-00) at tachometer and reset first dip switch in back of tach to up postion for 2 wire trim sender.

what year did they change the wirring harness?

[boats.net]

2005 and newer models.