Morris Minor Owners Club

Almost 2 years ago I mentioned that I had one front tyre wearing on the inside:
viewtopic.php?f=4&t=70490&hilit=tyres
Obviously the car hasn't been very far in that time and while working on the brakes this weekend, I had a good look at other stuff too.
The Track Rod End on that same side is relatively easy to move compared to the other side, so I'm thinking it really needs changing.

I see there are 2 different TREs, pre and post 1958, the earlier ones being 9/16 BSF, the latter ones 5/8 UNF.
So hopefully '55 Basil should be the early ones by several years, but just in-case he's gained a latter steering rack (like he has the latter brake cylinders) is there a sure fire way to identify the correct TRE, i.e. an obvious external difference in the pre/post 1958 steering rack?

OK, so I've measured the outside of the Thread as best I can on the few threads that are showing, and the Vernier came up as 13.9mm, with 14.2mm on the actual bar diameter.
According to charts I found, this is slightly under that of the diameter for the 9/16th BSF (14.288mm) and well under that for a 5/8th UNF (15.875mm) , I'm going to assume its the 'correct for year' steering rack.
So I guess that's a wrap on that question.
I'll leave this here in case it's of use to anyone in the future.