Picture into left side of Radiator

seems to go down into blue hose, then into
heater at bottom of photo, then in red hose
up to top of block.

Question: Where do I drain the radiator?

More vertical picture just behind left side of radiator.

Note blue hose which comes out from pipe at bottom left

Better view of apparent drain?

Apparent drain from below, going into 120-volt heater?

Upper fan belt assembly.

Question: Do I loosen nut between pulley and vertical
bracket or the hard-to-reach nut behind bracket,
between bracket and engine block?

As you can see the connector that clips on to the last spark plug
has broken.  (The wire came out of the back end of the thing
that looks like a wire nut, and I took the whole piece off.)

Question: Can I just repair the end of the wire, or do I need to replace
the whole wire, or do I need to replace the whole distributor cap?