Sync carbs on Tohatsu 2001 90

[jonathan_239s]

Where is the plug that i can use to put my carb tuner on to sync all 3 carbs.

IMG_4282.JPG

drive.google.com

Please help i need to sync them but i don’t know where i can plug them to sync them all 3 at the same time.
i saw that it’s supposed to be in the manifold but i don’t see it.
please see the photo and help me out
It’s making popping sounds right when i turn it on. is it bad gas or the carbs out of sync?

 

[pvanv]

Port side of inlet casting, and top for the upper. But frankly, I don't bother. If idle is set properly, you are all set. Popping could be lean of off time.