As I understand it, Shelby had always thought the V8-engined Allards were a Good Idea and thought he could make money from a similar lightwieght car with a V8. He had conversations with John Wyer at Aston Martin, but they had no interest in such a car themselves. He considered the Austin Healy 3000 for a while and talked to most of the car maunufacturers in the UK and Europe and then got involved with a Texan
oil guy, Gary Laughlin, who wanted to build a Corvette with an Italian body. Jim Hall got involved as he had a sports car dealership with Shelby at the time. They got three chassis from Chevrolet and sent them to Scaglietti in Modena, had them built up and had one each. Shelby and Hall acted as consultants but Shelby sold his car almost at once.
Either Chevrolet got annoyed that taking a chassis off the production line caused production to be interupted, or they were worried that the 'Italian' Corvette might be better than theirs.
Anyhow, they lost the chassis supply. (see the book Corvette Fifty Years by Randy Leffingwell, pages 158 - 166)
Shelby would have done a deal with Skoda if they could supply him with a body/chassis unit. He just ended up with an AC Ace because it had a lot of room under the hood and also looked quite nice. Don't they?