Well, as Jeff's pic of the diagram on page 15-8 shows, there is one wire coming into the AM/FM radio picture from upper right and going down into a 3-pin connector (and looks to be in the wrong position, it should be in the center connector); that is the unmarked/no color-called-out front speaker wire. As shown in my photos below, my front speaker green wire just has the metal connector, which I assume was pulled out of the correct 3-pin connector that would have a wider slot to plug the yellow power wire into (maybe they just shoved into rear radio speaker pin slot).
So, I found a correct front speaker wire with connector online here:
https://www.ebay.com/itm/112385775172
All I have to do is snip the end of the green wire and then solder it to the front speaker connector (which I believe is factory correct?), or I can crimp on a slide-on clip, and then my entire radio wiring harness routing will make sense (colors don't match references but the circuit will be correct). Strange that Ames doesn't sell a front speaker connector+wire like this.