You could experiment with a clunker body, burnishing with light steel wool in some parts... maybe small discs of 120 grit on a pencil eraser in some areas (twirl with fingers or low drill speed) dab some areas with sprue goo...then airbrush a few coats of metallizer. Would need to find and mix the colors (now discontinued) to get the verigated silvers in a raw mild steel body. Brighter areas could be lead work. Maybe overcoat with a wash of tamiya smoke to pull up the 'grain'.

Rodders Journal ran several bare steel hot rod centerfold cars, pretty darn remarkable work.