If you plan to go to bare metal on the entire cab eventually, then why are you so concerned about doing this partial spruce-up so perfectly?
I understand making it look right in the meantime, but perfection in not necessary for the short term. I would scuff it, prime it, and rattle can it for now, then do it over after you do the total strip down the road. I have made some dashes look absolutely awesome with Rustoleum rattle can products.
