I managed to buy an N gauge PCA cement wagon that didn't even have any couplers! AND I had a good look at it before I parted with the cash.

It was only when I got to the pub and sat down to inspect my new purchase that I noticed.
Hope you're feeling better soon Syd. I have problems with my knees myself. One of them sometimes clicks so much I'm beginning to wonder if I have wheel flats.
Get well soon.