I've also played around with adding a second sequence of signals from behind the trains (where they are in the pics), adding one a few tiles behind the one at the back of the train and another a little ways further down the track than that. Done that to the other side as well. I had some blue and ...

I'm certainly not putting the signals on the wrongs sides. I am getting effects, just not the ones I want.

Here's some images of my setup:

https://pasteboard.co/HKpDdpo.png
This one show the signal ahead of the stop (under my cursors crosshairs) and juuuuust at the back of the cargo wagon is the ...

So I encountered a problem where the iron vein I've been basing my factory on has all but dried up. There's a nice fat seam south, so I built a track going down to bring it up. Turns out, one train wasn't enough- as soon as it leaves the stop to get more, by the time it gets back my furnaces are ...