Mine is a Belair, not sure if that makes a difference, and they (the wheels) are body color. The Impala is tucked away, so I can't tell you on that one. Others will know!
On any model '61 Chevrolet except the Super Sport, the wheels should be body color on the front and low gloss black on the back side. The Super Sport got black wheels (front & back) regardless of body color.