A very new direction

[scottishlocos]

Lawrence

Glad you are modelling a Scottish layout and looks like a really solid plan you have.
For your DRS 66 I would have a look at the following wagons

Dapol Intermodal

Farish Intermodal Twin

Farish Nuclear flask

Farish Autoballasters (normally run in rakes of 5 wagons)

Farish ZAA engineers wagon often run in short rakes

Dave 

[Newportnobby]

I think the issue is Lawrence only has (and I'm guessing) about 24" on each hidden curve so with a class 66 there's room for only 2 or 3 autoballasters or 3-4 shorter wheelbase wagons.
I'm liking your suggestions though.

[Lawrence]

Lawrence

Glad you are modelling a Scottish layout and looks like a really solid plan you have.
For your DRS 66 I would have a look at the following wagons

Dapol Intermodal

Farish Intermodal Twin

Farish Nuclear flask

Farish Autoballasters (normally run in rakes of 5 wagons)

Farish ZAA engineers wagon often run in short rakes

Dave

@scottishlocos  thanks Dave, very similar to what @newportnobby has mentioned to me, I do like the look of the engineers wagons (US speak - gondola = hauls anything) not sure of livery though given this will be a private company doing the work and utilising the railway to provide supplies to a remote(ish) region.  Given my outline of the purpose of the railway, there will be no need for flask wagons or autobalasters, would love to find a short 20' container wagon though, may have to do some Rule #1 to fit my needs!

[njee20]

Yep, you won't find a UK prototype 20' Container wagon. Closest would be something like a PFA which carried a single 20' coal container.