I was aware of the origins of Llansantffraid Crossing box, but it happened to be just the size of signal box I was looking for. Nevertheless, I take your point about getting everything into the interior.
My roll model is Llanfyllin (below), but a scale model would require a huge amount of space in 7mm scale. I am cramming it into 14' X 3' and so with length and width massively reduced along with platform length, it seemed sensible to 'shrink' all buildings in order to keep everything in proportion. As an example, the small Cambrian signal box that was built a few weeks ago looks massive on my layout. But the biggest
thorn in my side was the goods shed. It overpowers everything, but it won't for much longer.
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