I'm starting to really dislike photbucket, you go look at a pic and they start booming you with adds. I also use it just not much anymore
Your serial number is 0F747372, if you out it in your signature along with the drive then it will always be there when you ask a question.
You found the manifold drains, the sensor on the starboard side is your knock sensor. It is attached using the Y-adapter shown to the right of your pic below. There should be a 1/4 brass pipe plug which is removed to drain the block.
On the port side you will need to remove this hose going into the power steering cooler and lower it into the bilge. This will drain the seawater pump, cooler and hose going to the thermostat housing. Also pull the brass plug you found on this side of the block.
Remove hose as noted to drain water pump

It might not be that close, but the pulley just looks close to the fuel fill hose.
