Tach needs 12v, a ground and a sender wire from the regulator. Reset the pole setting on the tach. The speedo needs no voltage except for the light it works off of water pressure at a port on the lower unit or a mounted peeto on the transom. These Yamahas start better if you pump the bulb up real firm. I have had to adjust the solenoid that closes the choke butterfly`s. You have to remove the air silencer so you can see the choke butterfly`s, hit the choke to see if they are closing all of the way. Adjust as needed.
“The world will not be destroyed by those who do evil, but by those who watch them without doing anything” GOD IS GOOD