The main engines are not too bad a moulded affair, there are resin
replacements that are far superior though.
The painting of these, like the almost all of the rest was just enamels.
The only place where acrylics were used was the white surfaces.
The engines were painted with Humbrol Polished Steel,
great paint as I have said before,
dries matt, buffs to a splendid metallic finish.
The more you buff, the richer the colour and finish.