kit-bashing a 1/25th scale model of my Dart.. need help

Oh I almost forgot.. I am sure there is more than one model builder on this site.. So I will also need some advice, my Dart will have a black vinyl top.. The model kit makes no provision for this.. Now I can kit bash the vinyl top trim or even just paint the trim on with a very fine brush and a steady hand.. however just painting the roof a matte black will not be enough in my opinion.. it needs to be slightly textured to give it that look of the vinyl... any suggestions on how to accomplish this?

and I imagine the Duster model that I rob parts from (or whatever kit it winds up being yielding the parts I need) will not go to waste.. I will eventually use it (them) to build a 'work in progress' type of model.. lol..
What Ihave done for years is to just use regular masking tape cut into sections like the real roof had . Works very well and I've got several cars I have won in competitions from doing them that way . Try it . Its real simple !!