I've now got a copy of "The Wrexham & Ellesmere Railway" and in it is a picture of the yard from behind the good shed - not the view I really wanted but it does show the scrap pile.

So Caia Road Goods only had 3 visible points from the goods shed to the road bridge - the crossover would be off layout.

I must admit it would work well in N gauge on two 5 foot boards, but I feel it may/could be effective condensed into (around) five foot, plus fiddle yard in 00 - with the option to have another fiddle yard the other side of the bridge for through running (a 9F on the oil train may be a problem though!).

I'll sketch it out when I have a spare minute or two. I've got a 5 foot board in the garage, so I'll see if it can be condensed into that space.

Although I'd like to try EM or P4, the cost of new chassis and motors for the 57xx & 14xx (and any other locos required) would be prohibitive, then there's my lack of soldering ability for the track. So I think it would have to be 00, as I have the track, points, locos and wagons...