I had a 90 Johnson that I let sit too long with fuel in the carb. I
took the carb apart (patience, digital photos of each step, and a good
handbook) and found "gummy worms" of jellied gas in each passageway of
the carb, particluarly the baseplate-like foundation of the carb body.
My boating life improved immediately.

Every time now I pick up a can of gasoline, I think Stabil fuel
stabilizer.

The carb is not magic, just a machine. Get good light, a big surface
with a towel over cardboard to catch minor spills and gunk. There are
some springs and small steel balls serving as needle valves in the
older one I worked on, and they jump if you don't move very slowly in
separating pieces.

The worst that can happen is that you screw it up and have to get help.
If you don't try, that's your starting position. I'd like to know how
it went.