[Scuderia_Turini]

Hello Robbin,
I prefer Photo-Diodes as they are slightly quicker to respond,  but those Photo-Transistors should work.   
The cores in that cable will be very fine and so difficult to work with. Here is an example of the kind of audio cable I use. Various lengths are available but I suggest that a 5metre length would be good. That would allow you cut it into a decent short length and long length sections and having the actual cables separate will make them easier to work with and be more robust than the pre-wired 9-pin cable.

Photo is my suggestion to fix the cable to the Ninco track. Inevitably the track will sit a bit higher than normal.  If nothing else make sure to cable-tie at the edge.

Leo