IF you plan to paint all the interior to match, you can wet sand those A-pillar pieces and paint them with the same enamel used on the metal pieces. Just be sure to bend your paper into their grooves. Knock all the gloss off of them. The flexible dyes for vinyl and plastics are great for those pieces that will be flexed.
The A=pillar trims are abs plastic and just like the instrument panel. They dont bend much before breaking.