Each to their own, but everytime I see something like this, I can't help but think it'd be cheaper to rip out the entire drive train, fab your own "Locost" chassis (a Lotus 7 type car), and plonk the running gear in and end up with a lighter car? There's even a book that guides you through it, though its based on using a Ford Sierra donor, but the principles are similar. https://www.amazon.co.uk/Build-Your-Own-Sports-Car/dp/1844253910