I think it's the Lamborghini engined test mule they tried before going with Ford after Honda told them they were pulling out.
I think it was late 1993. Senna tested it too and really liked it but the Peugeot deal came (Ron wanted to go French on French against Renault), Senna then went to Williams, Prost deciced to retire and Lambo ended up at Larousse. How things could have been different? Next
Sad to say , I actually remember reading the article where he said it . Oh . I think you mean how do you find the answer .