This is one of many variations of the La Saetta fiberglass sports cars designed and built by the Testaguzza brothers of Detroit, Gino and Cesare. This one sports the quite rare (as is always the case with these 'glass cars) fiberglass hardtop and owner chosen bumpers, tail lamps and wheel covers to suit his taste. The cars were offered from 1952 through an electric version in 1956 and were either kits for your chassis or completed cars.
A "proof" article at <<< link removed >>> has links to other La Saetta copy from the past.
I had located one of the La Saetta cars sitting on a Jaguar chassis in North Tucson, Arizona some 14 years ago but could not talk the owner into selling. They are certainly among the most highly styled of all fiberglass bodies.