Automatic gearbox knocking sound

The last magazine article that I posted had an interesting comment regarding a potential issue on the automatic gearbox:

I recognized this instantly, it was one of the points I highlighted when doing a buying inspection as per blog item 4, although I sensed is was coming from the front right.

https://erwinxjs.blogspot.com/2016/09/the-hunt-part-ii.html

1) Steeringpump noise and occassionly playing up.

2) Moving the gearstick into position (P/R/N/D) did not went smooth.

3) Engine idling high when running stationair in N.

4) The front right making noise, suspension? wheelbearing?

5) Airco not blowing cold air.

6) gasmeter not working (known already).

7) bonnet gasstruts failing

Can't believe it this was in 2016, times flies! In any case, the article describes it well, it's a knocking sound that manifest when firmly accelerating. At the time I figured it might be a suspension issue or a bad wheel bearing. I think I ruled it out already some time ago and I had bought cross couplers for the cardan as I suspected these to be worn out and causing this knocking sound. But I never replaced them. But reading this article I'm now more inclined this is the real issue. I definatly need to crawl underneath to car to see how and where this mount is fitted, likely it will be a tough job to have it fixed.

Also the fix of the ballpoints did not solve this knocking sound:

https://erwinxjs.blogspot.com/2017/03/upper-and-lower-ball-joints-replacement.html

Interestingly in this same blogpost I had also been in contact with the first owner, who happened to be a Jaguar car dealer. And back then he informed me that the gearbox was replaced at some point. I would expect he also replaced the gearbox mount - but maybe he didn't. 

Thinking about it, this might also explain item 2, which is fixed but still not to my satisfaction. 

HURRAY for the internet and other hobbyists. I couldn't wait and I hit this article instantly. So another item on my todo list:

https://bernardembden.com/xjs/transmount/index.htm

And one more great solution to remove gearbox mounting bracket:

https://www.jaguarforums.com/forum/xjs-x27-32/v12-5-3-he-gearbox-mount-easy-safe-removal-refitting-145478/