Its ok, but I would have taken it off and done the job more thoroughly. But each too their own. Regards D4KGP.Thanks for your input everyone, it is greatly apprceiated.
I had a good look at all four rear subframe mounts today, and the surrounding areas with Dert's comments about sills etc in mind. Thankfully, the old girl is still solid on both sides in that area, so that was a relief.
But I did find this on the Offside:
Which I have to assume was what the MOT tester found yesterday...
After a bit of wire brushing:
And finally straight after brushing on what little Black Hammerite I had left...
I will take a look at those lower arm bushes next weekend now, then take it from there.
Thanks again everyone.