This was still one of the dumbest things the NPS did, in my opinion. I know they explored the idea of doing hunts and thought it would be a logistical nightmare.
2 emm's different motors. New carbs, twice on the same 90hp. New fuel injectors on a different 90 hp. These motors had under 400 hours on each. My guess is to many idle hours. In my personal etec, I also had to do an emm. Since switching to Yamaha, 0 issues.
Why, is because I've worked with several different size and year Mercury motors and all have been junk. I've also worked with several Yamaha motors, never a problem.
I love these type of threads, the op's have had years to plan a hunt and don't have a clue on what unit to apply for. Then the fight is on when people give suggestions.