1981 245 b21 m46-

I'm trying to get my od to work again and am checking out the usual
things. The relay is good so I tried to check voltage at the
solenoid. Upon crawling under the car I noticed that not only is the
red wire from the relay (bundled with the yellow +) unplugged, the
insulation is cracked and split.

So, after I solder together a new red lead, where does it get plugged
in?

I also notice two more wires disconnected and dangling in the
transmission tunnel. They are a blue/yellow and a black, both 12-14
guage (or so), both with female connecters. They trace back into a
fat bundle under the dash. Any idea on what these are? Either they
connect to some option my car didn't come equipped with or else I've
got problems I don't even know about.

Thanks in advance.
-Eric