I have always thought the sills were painted satin black although I have been reading a few early press reports saying the sills are painted in a bituminous type of black ie. (shultz)
just thinking about what to paint the sills with on the white one.
the satin black obviously looks nicer
http://mytr7.weebly.com/
1981 DHC 2.0 Litre
1980 DHC pedal car
1976 FHC 2.0 Litre