[svxistentialist]

I think it is a good or maybe even great idea, and I won't throw cold water on your party.

In common with 3 or 4 other responses above I do think that the business case is not there. You will not make enough on each car. However, were you to build one for yourself as a show car, as an exercise to show what can be done, then that would make business sense.

You would have a vehicle for prospective customers to test drive. You could get magazine exposure by loaning it for drives and photo shoots.

You could then come out with a range of upgrade prices for customers to buy particular levels of change. I leave it to you fellows to determine the levels. Define the top level [twin-turbo mid engined ] and define Level 1, price the rest in between

You will go far, Glasshopper.