That engine is a 4 cylinder 90. Previous models were three cylinder but when NMMA had all manufacturers rate horsepower at the prop in 1982, Chrysler simply down-rated their venerable 105 to a 90.
As for winterizing, store the engine vertically and change the lower unit oil. If it is milky, find out where the leak is and change the seal. Since the engines are self draining when vertical, there is no need to flush or use anti-freeze. You can use fogging oil in the carbs if it makes you feel better but if the engine was run regularly, there will be enough residual oil in it to protect it. I never fog any of my engines up here in PA and they do just fine through the winter.--the choice is yours.
That's about it. Outboards are relatively easy to store.