Next weekend I'm hoping to be hanging my '87 Merc. 115 on the back of my newly restored boat. How do you measure to find true center on the transom? Finding port to starboard center seems easy, but how do you make sure the motor is mounted straight up and down, not leaning - even slightly - to one side? Another way of putting it is, how do I find the true plane? Thanks for any insight.
TG
TG