G'day everyone and a big hello to Maestro Peter Butler,
Captain Plod is building four Brandbright carriage kits. (two kits at a time so his cranium does not have a melt down)
He has anxieties!
He would be happy to get to this picture

So he needs to ask for some advice and or confirm that he is on the right path with these. He has tried researching forum threads and the ether net but he cannot form up some conclusive answers to his anxieties.
(Garden Railway Club, an article by Dia has been the best one he has found so far)
He intends to first sand and file every edge/shoreline to remove most of the black LASER cutting burn. Then to get a smooth fine outside finish Plod launches his first attack to the bare outside ply sides by rubbing down with 400 grit, then sealing with Rustins Quick Drying MDF clear sealer. Rubbing this back with 400 or 600 grit. Applying Auto lacquer colour paint via spray can. Then rubbing back with 600 grit for 3 -4 coats. (Plod will do some test panels on spare ply to ensure the paint finish works as intended) Plod is a narrow minded metal worker so he has never been here before with gloss paints and ply carriage walls. The thin outside onlay skeleton he was going to spray a contrast colour, then when the coats are dry glue this to the outside walls.
Final overall coat will be a gloss clear varnish. (before the glazing is added)
* However what would be the best glue to glue these painted overlays to the finish painted outside walls?
He is pondering how to obtain a clean neat sealed edge of the only to the outside carriage wall.
* Or does he glue to all up and then again paint and chase the edges with a fine brush ?
*Or do you have suggesting to how he might do these processes differently?
Cheers from Captain Plod's Therapist.