I followed the Exact same process as my infantry so far for the metallic yellow:
1: spray silver and then seal with matte varnish, then wash with nuln oil
2: wash panels with cassandra yellow
3: wash panels with cassandra yellow again
4: a coat of Yriel yellow glaze on the yellow panels
5: two coats of badab black on other paneling
6: sponge on battle damage and weathering with black
7: highlight black edges and fill in battle damage with a bright silver, I use a flat brush for this
8: fill in any other details to taste!