The device from TS turned up yesterday (
https://www.teleskop-express.de/shop...hp/info/p11188) and I've just had a go at using it. Very easy to use once I got it installed. Something to keep in mind - it's not threaded, so you have to put it into a 2" holder - and it's a very tight fit. That's useful because it's not going to move once inserted. In fact, I'm leaving it inside the holder "forever", since I can't remember the last time I used it for anything else.
After I made the adjustments, I put the tak scope on, and it seems to agree with the TS collimator. Proof will be in the star images, which I am hoping to try tonight.