More stripping best way of removing bitumen?

[ozonehostile]

i use an air chisel and either thinners or acetone to remove the residue left over.

depends if your going to respray the area after aswel because then you could use a combination of air chisel, drill wire brushes and angle grinder flap discs to remove absolutly all of it (including the paint)

i think you should remove the paint and respray the interior the same gloss black as the exterior of the car, would look mint then