Winterizing inboard [raw water system]

Question
Hi Ron,
I have a 2003 Larson with a 3.0L Volvo inboard engine. What is the best way to winterize my boat? I have a good idea but want to make sure I don't miss any steps. I have located the block and manifold drains and opened them. Also I removed the lower hoses to the water pump and drained them and replaced. How am I supposed to run the biodegradable antifreeze through the system. The engine does have a engine flush hose to connect a garden hose.
Any info will be appreciated. I did try using "muffs" on the water intake ports to pull Antifreeze from the jugs but that didn't work?
Thanks, Rocky

Answer
Hi Rocky...Thank you for selecting the undersigned to respond to your question.  

I'm not a mechanic but, sounds like you're on the  right track, and now that the system has been completely drained, I can't explain why using the muffs on the outdrive wouldn't work, so use the alternative flush hose, as you call it, to introduce the antifreeze, but first make certain all drain cocks are closed, and that antifreeze actually becomes discharged, which will let you know it fully circulated the engine and exhaust manifolds. Also drain/replace the oil in the lower unit of the outdrive.

Safe Boating
Ron