The slick wheel covers are an easy one. Go buy a roll of silver Monokote at your local RC hobby shop. Streatch a 2x2ft sheet across the rim tack it down around the perimiter and shrink with a heat gun. If you've never used this stuff, test it out on some other circular object. You'll have plenty.
You'll want to be careful about how much heat you use to tack it in place.