12months is not along time to store a engine.We quite often have motors in storage
for for that time plus, awaiting damaged hulls to be repaired.I would do the following.
1. Flush all waterways with freshwater.
2.Remove pump impeller then crc area & replace faceplate making sure to grease screws.
3.Oil change engine & leg and replentish
4.Remove air cleaners then squirt a teaspoon of clean oil into each cyl while turning engine over.
5.Remove prop from leg &saturate seal area with crc.
6.remove valve covers & cover rocker,valve area with clean oil.
7.oil & crc leg input shaft area and tape up spline.
8.loosen of alt belt
9.crc all externals & clean engine mount rubbers.
10. Seal up air intakes & exhaust openings & cover leg input shaft & output shafts & seals
11. exercise & gease leg inlet valve.