It feels longer than three weeks since I last posted on this thread, but before revealing the latest news, here are a few catch-up shots:

Apart from the rusty metposts - that are nothing to do with us - I am quite pleased that the finished wall does at last look nice and tidy!
Mr. O has been quietly busy in the mean time... including apparently growing to just over seven feet tall...
OK., so he was standing on some hidden blocks to reach the top...
with brushloads of super, satin, spot on, carefully colour matched, LNER (1937) Green paint!
Incidentally, I did not plan this, and it was only later that I discovered that Mr. O thought he would surprise me by secretly borrowing from my "samples" and mixing up a batch at his workplace!
Despite what is claimed by various sources, this particular (LNER) shade also precisely matches some original (of which I am reasonably confident) samples of Southern Railway "Green No. 3A".
Whatever, I am very, very happy with it... the colour rings all sorts of bells, and anyway has a particularly nice, historical feel about it too!
Finally, to today's latest:

At last, 18 metres of 8mm x 25mm steel for the tramlines!
Much fretting, and finally finding this stuff took a while. Although I have sufficient aluminium rail already in stock, setting it in concrete is an absolute no-no - unless I wanted to sit and watch it turn into two, long streaks of white powder that is! The nearest equivalent in steel flat bottomed rail from the regular miniature railway suppliers would have cost around £200 after delivery charges... so that was emphatically another no!
I searched for any local steel stockists for anything appropriate, and found "good old" Mackays of Cambridge! Their online prices came to just over £120, plus delivery. I gulped, and then decided I probably had little choice but to go for it... with one caveat: I wanted to see it first.
Took a trip on "Rich's" bus into town, inspected the metal, and said "yep" to the nice man at the counter!
"Eighty quid... and a fiver to deliver mate" says he!
"Done!" I replied!
With my abysmal grasp of mathematics, I might well have been, of course, but I am sure by half the amount I would have had to cough up for "proper" rails... and then only to bury all but the tops of the hefty investment in cement?!
Pete.