as far as i'm aware, no elbow grease need apply, the vinyl is thick enough to cover the dimples with out leaving a mark. the ones i have to test on havebeen chewed up by their owner with a dremmel to the point where painting isa not an easy resurection . so hoping the vinyl will do the job.
it should be the same as the DI-noc stuff the others hlike BM have used on their dash and as far as i'm aware they didn't rub them down first.
No need to do any prep with Di-Noc or similar, just make sure the surfaces are nice and clean and it covers up any texture underneath nicely
Added bonus of going back to stock if required