Thank you Carnut, you gave me the chance to find back my source and fix the extraordinary story of Ray Russell!
He's been featured at least 6 times in some Popular Magazines and his son is still out there with many interesting memories.
After his 1st plastic bodied car in 1941, he built a similar car, but with plywood body in 1943. After his adventure with the MG TA-based alloy-bodied Gadabout in 1944, he got back with a plywood-bodied car. In 1945 he was working on hydraulic powertrains and in that year he built an interesting aluminum-bodied, suspension-less motor scooter. In 1947, the same powertrain (called Hydrolic Drive) was used for this small sports car. He was also the designer of the Detroiter and a restyled Ford in 1953.
(but I found also an hi-res picture of the puzzle car and, surprise surprise, you can read '1942 gadabout' on it.)