Questions about Appen and Bea-Dawe Routes

What British equipment would I need to run in order to replicate the steam era on the routes? Or how about the transition era?

Each region would have its own railway company and it would depend on the time period.

Which kuid are you looking at?

Cheerio John

For the Bea-Dawe route, I'd like the early days of nationalization, before the equipment was relettered to BR, as that would mean that I could run LNER-lettered (i.e. Mallard or Flying Scotsman) locomotives on what previously only seen GWR equipment. Or I could go model post-1955 and feature their unique diesel-hydraulics. Given that Class 55 Deltics appear on the Appen route, I think that Appen is part of British Rail's Eastern Division, which is Ex-LNER. I'd take the steam era for Appen, so that I can run Mallard or Flying Scotsman on it.