That pic you put up is a looper intake not a crossflow intake. The OP has a crossflow which will have traditional carbs. So no it will not have adjustments.
You will have to google a little bit.
High cliff/Sherwood Marina
Jefferson Park Menasha
Doty park Neenah.
And there are other ones those are 3 to start with.
And Oskosh itself will have a couple for sure along with Fon Du Lac
If you want to go faster buy a 77 or later 9.9 hp motor. It is a significant jump in power compared to the 9.5 hp. The 9.5 will never be the motor you want it to be.
That motor should have a cap on the hood for 2 strk oil ONLY. The cap on the boat should have gas ONLY unless the oil injection doesn't work or has been disabled. If it has sat for a while take it to a competent Merc Mechanic who is familiar with the 2+2 motors.