Got a used kit the last time I was in the UK. I'd guess a lot of these are surplus due to the owners buying new un-maintainable cars.
As far as I can tell its complete apart from the bottle of cleaning fluid, but the connector to the ignition lead has a threaded end which doesn't, on its own, make a good connection.
IIRC motorcycle spark plugs often have a threaded end which takes a removable nipple (dunno why, perhaps there are more than size nipple?) so I went around some motorcycle places to try and get one, and as usual got the M word (meio = I don't have, OR I can't be bothered. Go away foreigner) everywhere I tried. I suspect the Colortune might have been confusing them.
The last place I tried harder and waved one of their spark plugs around a bit, and, using smartphone translation the guy seemed to be saying that the spark plug nipples were bigger (presumably meaning the threaded hole is bigger.)
IF this is true, it raises a couple of questions
1) Why TF would colortune supply the thing with a non-standard thread? Seems unlikely.
2) Could I get one of these allegedly big female nipples (Ooer Mrs) and fill it with solder, then drill it out and get the adaptor thread to self-tap into it?
3) Failing that, could I use a bit of, say copper brake tubing filled with solder as a link between the adaptor and a standard car male-thread nipple, shown in the picture above?.
2 and 3 are both a bit of a hassle but if needs must...
I've got an old motorcycle plug with a threaded terminal somewhere. I'll take that, rather than the colortune with me if I have to do the rounds again, though that'll probably have to wait until after CNY.