I think you got an answer in the other topic you started about this:
Correction, there isn't a exit nipple & water hose on the crank case or adjacent areas in newer 40C. so must have a factory cast inside/outside middle leg water peeing port, same as the 18 HP model. In older 40C it's Mission Impossible installing one.
Happy Boating
I changed this topic's title so someone looking at the topics list will know what you're looking for.
Since you've gotten a few responses in the other topic, that suggest it's not an simple or easy drill and tap to add a port, you may be digging a dry well. If you didn't get details or a how to in the Tohatsu forum, I doubt you will here.
FYI: for motor topics, I'd strongly suggest you post a model# if you want help w details about YOUR outboard specifically. Serial# too, to make sure you get the right info if there was a mid-year change that didn't create a new model. Good luck
