Hi Ben,
In answer to your questions:
>If you hadn't seen it here, how else might you be most likely to get news of such a scheme? Club? Magazine? Other?<
To be honest I get most of my info from the main manufacturers websites, supplemented by occasional visits to this site and the websites of prominent shops like Hattons. I also get passed info from a couple of friends that are also enthusiasts and modellers. I used to buy magazines a lot, but don't as much now.
>It stands to reason that at least one should be suitable for an early 8-car version. Out of interest, what would be the highest appropriate number for this?<
I believe 001-044 were delivered as 8-car sets originally, so there's plenty of scope there! For me personally, a lower numbered unit would be best, say one of the first dozen or so, but it wouldn't be a deal breaker if it was numbered higher.
Cheers
Harry