Worth keeping in mind the GT40 program was to "kick Ferrari's a**", on pretty much a 'cost no object' basis. As such, there was a focus on building to suit racing requirements - light weight, stiff structure and mount points, etc. - which meant monocogue stressed panels and structures, hand fabrication, tons of rivets, etc. This was never intended to a mass-produced vehicle - it was a race car. Translating that to something that could be affordably mass-produced to achieve economies of scale is going to be very difficult, if not impossible - unless the transformation results in a radically different platform (e.g. fiberglass body on a tube frame). For that model, take a look at Factory Five's GTM - very different than either a Cobra replica or a GT40.
http://www.factoryfive.com/kits/gtm-...chassiscontent
For that matter, Ford and Shelby stopped making the original Cobras because they couldn't make money on them, and they were pretty simple automobiles. Arguably they could have made the Cobra profitable by switching to fiberglass bodies instead of the hand-hewn aluminum ones, but we'll never know, will we?