I have a 2006 4.3 GL-E engine which I'm winterizing for the first time.

I did not have access to a hose, so did not use the engine flush connector to run water through the engine for 5 minutes to "ensure drain ports are open".
What are these "drain ports"?

Also, the shop manual instructions (attached) I have says CAUTION ...
"If a garden hose with fresh water supply is unavailable,
you must remove the hose nipple(s) from the engine to
drain the engine block. To ensure all water is drained,
clear the drain hole with a piece of wire. After the engine is
drained reinstall the hose nipples and flush adapter as
removed. The exhaust manifolds are drained as described
previously"

What hose nipples are they telling me to remove?

Any help would be much appreciated!

 

The drain plugs are on the bottom of the block just above where the oil pan is attached. You can feel them. Typically drain plugs, but sometimes people have put a small valve to replace the drain plugs

Sometimes a chunk of rust from the cast iron block gets clogged around the drain hole thus why they suggest one to poke a small screwdriver or nail into the hole to clear the chunk of rust and allow all the water in the block to drain.