Help! As I was hoisting the outboard off my
dinghy getting ready to put it away for the winter, the snap
shackle I was using opened and I dropped it in the briny water of the Potomac river, DOH!!!

(Ever had that little voice in the back of your head saying you should be getting help and should secure it better, yeah, don't ignore that voice!)
So after it sunk to the bottom I was able to scavenge up a grappling hook and fish it out. It is a 15hp Yamaha 2-stroke. I brought it home after thoroughly washing it off with fresh water. I removed both spark plugs and got most of the water out of the cylinders. Now it is drying overnight.
What should I do to save it and save myself from having to buy a new outboard?