Don't blush you all deserve it, I'm just copying your ideas you all had the imagination, as to the Terrier all the RTR ones drive the back axle so don't lend them self well to converting to 0-4-2s, the 14xx as well as driving the second axle also has slightly bigger wheels which are more inkeeping with the Caley tanks.
As to coaches I'm buying in some as and when I see them but I'm looking for ideas for older smaller stock for example can any thing be done with the old Triang clerestory coaches I'm sure I saw on here some one had converted them to look like Caledonian 45' coaches these also turn up on Ebay quite ofen
To quote an old friend who used to say "A blind man on a galaping horse couldn't tell the differance"