I bought this kit from Mike Williams Models and have tacked it onto the end of this post as a, it's another North British and b, it will end up as one of James Nimmo's coal wagons.
First picture shows the kit assembled and ready for the under coat. I applied three coats of sanding sealer to the sides only, sanded down between each coat. The idea behind this was to give a smoother surface for when the transfers go on and not have the grain of the wood showing through. If the grain was to scale, it wouldn't show up anyway.
Second picture shows the Acid Etch Primer applied. Tomorrow, if the primer coat is okay, I'll spray on the top coat.
Jon