cut out all the bits and offer them up to the correct position before glueing

I used super glue to stick them down but you could also use plastic weld 

work your way though the bits using the edge of the base as a guide

when stuck down give the surface a light sand with fine paper or scotch pad

apply a watered down dark acrylic paint before removing the excess with a cloth 

using a chrome pen, paint of silver leaf apply to the edges to give the illusion or scuffed metal