guessing the 470 engine
change oil and filter
change gear lube
check that the Anti-Freeze is good for -35 to -40
drain the heat exchanger (aft plug)
pull end caps off heat exchanger and clean out
replace the zinc as needed
use a funnel to run AF down the line to the PS cooler and raw water pump
pull the drive to check alignment, gimbal bearing, u-joints and bellows