Yokay ,Thats half the battle .
I would ........
drain the float bowls on the carbs and the fuel filter to clear any crap and water
Change the oil in the gearcase and fit a new pump impeller
take the prop off and clean and grease the splines .
then just check over things like fuel lines and wiring looms for loose fittings , clean and lube all the linkages for the shift and throttle .
grease the steering and tilt pivots ( there should be grease nipples )
Other than all that just give it a good clean around the powerhead . I use a cheap paint brush and a couple of cans of cheap water soluble aerosol degreaser and rinse it off with water ( hot is best as it heats stuff up which then dries off better ) blow off with compressed air if you have it and spray some corrosion inhibitor ( marine CRC , WD40 ...whatev ).
Run it in a tub rather than muffs if you can , check water cooling indicator , gear shifting and make sure it doesnt overheat .
When you get it in the water dont make a bee line for the horizon untill your sure its going to stay running .
Post a vid ( with sound )of you cold starting it and idling and of the powerhead while idling and if we spot anything wrong Im sure someone will say something
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