i would try to buy extra hellcat specific interior trim if there is such a thing. as a owner of a 08 bullitt mustang i am already having trouble buying some parts. ford stopped making bullitt specific parts shortly after production on the cars. a bunch of the parts are already being reproduced, but nothing beats NOS parts.
in my opinion the bullitt has cool dash panels, they went discontinued in 09. thank goodness i stocked up on those parts. i had a complete set of the dash panels NOS. someone with more $$$ than brains paid me more for the dash trim than what i bought my car for.
at every swap meet i go if i see a bullitt specific part i buy it even if i don't need it.i also regularly scan Ebay for bullitt specific parts, if i find them i try to buy when i can.. i would suggest you do the same.