Hi All - Thought I would close-off this thread. Well only part success has been achived!
First the wishbone/trailing arm bush, which I thought would be the easiest (sorry Bob). Is only for the shock absorbers, does not, and will not fit the training arm. Marking on the original part indicated it was a TRW Joint 024 0007 633 009 653 - Which is not manufactured anymore. Those in the know have told me that the bush is metallastic, which means the inner part of the bush needs to move with the travel of the suspension. So, a polybush could not be used. Polybush never even replied to my query so have forgotten that avenue unless someone informs me with further recommendations. Finally, did look a rose-joints but could not find a suitable replacement ( maybe someone else can pick this up?)
Secondly, the outer joint is a standard track-rod end. Original was also a TRW joint 022 0002 312 009 - Again, not manufactured any more. However the Fai Joints SS699 /SS698. fit perfectly, and the taper matches the hub.
So, yes the outer joints can be replaced. But the inner not at this stage.
Finally, my thread on the shorter trailing joints.
https://www.the-t-bar.com/forum/9-mgf-tf-pitstop/97262-another-rear-trailing-arm-question-but-the-short-one-this-time
Yes, the adjustable ones can replace the fixed. So that thread is also now closed.